|Al-Shabab has been accused of a spate of kidnappings and cross border attacks over the past few months [EPA]
At least two people have been killed in an attack on a church in an eastern Kenyan town, amid a spate of violence and and cross-border attacks, police have said.
Leo Nyongesa, the country's police chief, said on Sunday that a woman and her two grandchildren were also injured when attackers hurled a grenade at the Pentecostal Church in Garissa late on Saturday.
The house near the entrance of the church that belonged to a church elder had been bombed, Ibrahim Makunyi, the head pastor at the church, said.
"One of the dead is a member of the choir, and the other is the son of the church elder,'' he said.
Police have opened an investigation, but no arrests have been made, Nyongesa said.
Charles Owino, the national police deputy spokesman, said that Garissa is a predominantly Muslim town, adding that "those responsible for the attack could be [religious] rivalry".
"It could be al-Shabab sympathisers, you can't rule it out. Anything is possible," he said.
He also said that a partially exploded landmine had been found elsewhere in the town and was taken away by anti-terrorism police.
Last month, Kenya sent troops into neighbouring south Somalia to fight al-Shabab, who it accuses of being behind a spate of recent kidnappings and cross-border attacks.
The armed Islamist group, which has denied being behind the kidnappings, has vowed to retaliate in response to the military action.
Owino told the AFP news agency that attacks of this kind will not weaken Kenya in the fight against al-Shabab.
"We will solve the problem of al-Shabab once and for all. We will keep tracking them until we are able to hand over Somalia as a safer place to its law-abiding citizens," he said.
Garissa is about 330km northeast of Nairobi and about 70km from the Dadaab refugee camp where a police truck escorting a UN convoy struck a landmine on Saturday. The device did not detonate.
"People are not venturing out to pray for the [Muslim feast of] Eid al-Adha as there are too many security personnel moving around," a local journalist said, adding that security personnel have been searching the town for explosives for the past week.
The population of Dadaab camp, about 80km from the Somali border, has swollen to half a million refugees this year because of famine in Somalia.
The spate of attacks, including one on Swiss tourists on Friday, could deal a blow to Kenya's tourism industry which has only just recovered from the impact of post-election violence in 2008.
On October 13, two Spanish aid workers were seized by gunmen in broad daylight from the Dadaab camp.
On October 1, gunmen snatched disabled French woman Marie Dedieu from her home on the Lamu archipelago. She later died in captivity, French officials said.
In September, armed men seized British tourists Judith and David Tebbutt, who were holidaying north of the Lamu archipelago.
David Tebbutt was shot dead while his wife was captured. She is believed to have been sold to pirates in central Somalia.