Police in Tunisia have launched a nationwide search for accomplices, who may have helped the gunman who carried out Friday's deadly attack at a popular resort in the city of Sousse.
The student who massacred holidaymakers on a Tunisian beach and at a resort hotel acted alone during the attack but had accomplices who supported him beforehand, an interior ministry official said on Sunday.
Police were searching nationwide for more suspects after the killings of at least 38 people in Tunisia's deadliest ever such attack.
The attacker's father and three roommates were detained and being questioned in the capital, Tunis, interior ministry spokesman Mohamed Ali Aroui told The Associated Press.
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The attacker has been identified as Seifeddine Rezgui, a 23-year-old aviation student from Tunisia's Kairouan University where he had been living with the other students.
The attack was claimed by the Islamic State of Iraq and the Levant group, but Tunisian government has disputed it.
"We are sure that others helped, but did not participate," Aroui said. "They participated indirectly."
Investigators believe the suspected accomplices provided the Kalashnikov assault rifle to Rezgui and helped him get to the scene, Aroui said.
On Sunday, armed police began patrolling the country's beach resorts after the government said it would deploy hundreds more inside hotels in the wake of the attack that is likely to hit Tunisia's tourism industry particularly hard.
New security measures
Friday's attack on the Imperial Marhaba Hotel shook this North African nation that thrives on tourism and has struggled since its 2011 revolution to be the one Arab Spring country that succeeded in transitioning from authoritarianism to democracy.
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Tourism Minister Selma Elloumi will meet with foreign ambassadors to lay out new security measures for tourists.
At least 15 Britons were among those killed, the most serious attack on the British since 52 people were killed in attacks targeting London's transport network in July 2005.
Britain's Foreign Secretary Philip Hammond said it was highly likely that "a significant number" of the victims yet to be identified would be British.
Britain has deployed senior detectives and forensic teams to Tunisia.
In updated travel advice, the UK's foreign ministry urged those who remained in Tunisia to be vigilant and said there was a risk of further incidents.
Hours after the attack, Tunisian Prime Minister Habib Essid announced a series of measures, including closing 80 mosques not condoned by the state.
Source: Al Jazeera And AP