Nairobi, Kenya - When Kenya's security forces knocked on the door of Abdinassir Ismail's house during a counter-terror crackdown last May, little did he know that they would ask for a bribe.
"There was a bang at the door followed by a loud command: 'Open the door,'" recalls 36-year-old Ismail.
Six policemen stood at the door and asked for his identification papers, he told Al Jazeera.
The group were part of "Operation Usalama [peace] Watch", launched to hunt down people suspected of having links to Somalia's armed group al-Shabab, which is blamed by the Kenyan government for a series of deadly attacks, including last September's siege on a mall in Nairobi that left 77 people dead.
"I showed them my refugee card [registration certificate from the UN refugee agency, UNHCR]. One of them kept interrogating me while others ransacked the house," says Ismail, who is originally from neighbouring Somalia and has lived in Kenya as a refugee for 17 years.
"The policeman alleged my refugee identity card had expired. The truth is that it was still valid. He asked for a bribe. I had 1,000 shillings, equivalent to $12."
Life turned upside down
Before the crackdown, life for Ismail in Dadaab refugee camp, one of the world's largest, and home to other refugees from Somalia, was relatively peaceful. The counter-terror crackdown turned it upside down, he says.
Ismail says that even after taking the bribe, the police arrested him, setting off a 15-day ordeal for him at what is now called Kasarani "Concentration Camp", Kenya's version of Guantanamo Bay, the US detention centre in Cuba.
I do not know how much but am certain they paid something. The last detainee was released at the gate of the police station.
Since April, the Kenyan government - which sent troops to Somalia in 2011 to rein in al-Shabab - has ordered all refugees in urban centres to return to camps in the north and east following a wave of terror attacks and threats across the country.
Ismail's charge of extortion against security forces has been corroborated by Amnesty International, the London-based rights group which slammed the operation, saying it was carried out in "blatant" disregard of international law and the country's constitution.
"Kenya's Somali community is being scapegoated in a counter-terror operation which has seen thousands subjected to arbitrary arrest, harassment, extortion, ill-treatment, forcible relocation, and expulsion," the group said.
Security forces have previously come under criticism over looting. The looting allegations against them started to make rounds shortly after the deadly siege on the Westgate shopping mall and have continued to haunt security forces in their counter-terror operations.
Last year, the head of the Kenyan army admitted that soldiers who fought al-Shabab at the mall had looted mobile phones, cameras and battery chargers, although he had initially insisted that they only took water from the supermarket.
But police dismiss allegations of extortion and insist the crackdown did not target the Somali community.
Masoud Mwinyi, the spokesman for the Kenyan administration police, tasked with securing government installations, said officers accused of extortion face disciplinary measures.
"People can make complaints here and there but they have to be verified ... so that we can have a basis we can start from," he told Al Jazeera.
The accusations have persisted, with some of those arrested saying they had proper identification papers but were detained anyway.
Local trader Mohamed Ahmed Kulmiye, 40, says he was arrested and detained for eight days after showing his identity document to the police during the crackdown.
"They arrested me at dusk. I had to trek. They patrolled every street, arresting more and more," Kulmiye says. "They arrested me along with 13 other people, most of them Somali and Ethiopian refugees."
All of those arrested alongside Kulmiye were released after paying bribes, he said.
"I do not know how much but I am certain they paid something. The last detainee was released at the gate of the police station. They did not ask for a bribe from me. I am a Kenyan, my documents are genuine and I had nothing to worry about, so why should I pay a bribe."
At least 200 Somalis have been deported to Mogadishu, the Somali capital.
When Somalis show their documents they ask them where they were born, their identification and serial number, some officers even pocket others' identity documents. To other Kenyans, no question is asked once they show their identification. For us its either you pay something or you are taken to the station and stay there for days.
The first batch of deportees in early April included 82 Somali nationals; the UNHCR and rights groups condemned the move.
Interior ministry officials say they will deport all unregistered Somali nationals in response to a wave of terror attacks.
Ahmed Ali, 23, a high school graduate and a resident of the mainly Somali neighbourhood of Eastleigh in Nairobi, believes all Somalis face discrimination while in police custody.
Ali, who was arrested during the operation, dismisses the government's claim that the security operation does not specifically target the Somali community.
"They are targeting the Somali community. Police ask for identification documents [and] when you show them, they say it is fake and they want you to accompany them to the police station."
Police spokesman Mwinyi insists the public should be given the best service even if there are security operations going on.
"Any members of the public who feel aggrieved by the way they have been served, they have been harassed or officers have asked for inducement or extortion of some kind, have always been asked to report," Mwinyi says.
Ali gave a first-hand experience of the police forces' underhand tactics.
"When Somalis show their documents they ask them where they were born, their identification and serial number, some officers even pocket others' identity documents. To other Kenyans, no question is asked once they show their identification. For us its either you pay something or you are taken to the station and stay there for days," Ali said.
At least 5,000 Somalis were arrested and arbitrarily detained at the Kasarani sports facility, but Mwinyi says the centre now receives very few detainees.
"That is due to the improved security situation now in the country, particularly Nairobi, and also more people are carrying their documents," he told Al Jazeera.
Ismail says when they took him to Kasarani for screening, no screening was done.
"Trucks kept coming, bringing more people to the stadium," said Ismail, who managed to escape twice, once from the detention centre itself and later from the Dadaab Refugee Camp after a fortnight.
"The police officers at the door were so exhausted. I used that chance to get away with the help of a man who came to the place looking for his missing family members. The man helped me escape through the backdoor without being noticed."