Kenya's top cop now says a deadly attack on a church in Nairobi appears the be the work of al-Qaida-linked terrorists.

Police Commissioner Mathew Iteere Friday released a photo of the main suspect, known only by the alias Amar. Police officials said Amar is a native Kenyan but trained with al-Shabaab, a Somali militant group with links to al-Qaida.

Iteere also said an al-Shabaab leader named Sheik Ismael Ali claimed responsibility for the church attack while preaching to followers in Somalia and vowed to send suicide bombers to Kenya.

Last month's grenade attack on God's House of Miracles International Church killed one person and wounded 16 others. Police officials initially said they thought the attack was the result of strife within the church itself.

A report by a panel of United Nations experts issued last year warned al-Shabaab was trying to recruit new members from outside Somalia, and was focusing on other East African countries.

The Associated Press said Iteere warns Amar is just one of a number of Kenyans who are returning home after training with al-Shabaab. He says many of them appear to come from a slum in Nairobi, the border region near Somalia and areas along the coast.