Ugandan police are holding as many as 20 Somalis and several Pakistanis in connection with the bomb blasts that killed 76 World Cup football fans last week. Uganda's ethnic Somali community is on edge as security services go on maximum alert ahead of this week's African Union summit.

Community leaders say a joint police task force has detained Somalis living in several Kampala neighborhoods in recent days.  Others have been taken into custody at a refugee camp outside the city.

A police official, however, says there has been no breakthrough in the investigation into the July 11 suicide bombings.

The Somali insurgent group al-Shabab claimed responsibility for the twin bombings and has threatened to carry out more to retaliate against Uganda.  Uganda is the main troop contributor to the African Union peacekeeping mission in Somalia.  Kampala is on highest alert with more than 25 heads of state due to arrive for an A.U. summit, starting on Sunday.

Hassan Roble, deputy chairman of the Somali Community Association in Uganda, says his organization supports efforts to round up al-Shabab suspects.  He notes at least one published report saying that police believe more suicide bombers are in hiding in the country.  But Roble says the job is complicated because al-Shabab is a multi-national group. "Al-Shabab [members] are many types, not only Somalis.  There's even Pakistan, Afghanistan, Muslim community [members].  So you cannot easily discover these people," he said.

Most of Uganda's ethnic Somali community is considered fiercely anti-al-Shabab.

Prominent journalist Ahmed Omar Hashi fled to Kampala after he was the target of four al-Shabab assassination attempts in Mogadishu.  In one attack, he was badly wounded and a colleague was killed.  He says the bombings have renewed his fear that an assassin is lurking in Uganda's refugee community.

"That person can hide [among] the people.  And I don't know who he is; no one can be sure.  But I know the one who did that [suicide] mission is a danger to all the people.  He is a danger to Ugandans, to everybody in Uganda because the Somalis, they fled from Shabab," he said.

Ethnic Somalis say they have felt a double sting from the July 11 bomb attacks.

Ali Mohammed, who has lived in Uganda for 20 of his 28 years, says first he shared the nation's grief, then he suffered the suspicion of many Ugandans who blamed Somalis for the massacre. "I feel sad when my brothers of Uganda were devastated, and for somebody to blame me again.  These ordinary Ugandans, sometimes they can just bring these motorcycles close to you and can call you, 'You're al-Qaida.  Why are you walking along the road?'   We feel like we are called killers," he said.

Ali Mohammed says the suicide bombings have permanently changed the way Somalis in Uganda see themselves and the way others see them.

Several people interviewed for this report noted that, in much the same way as the 2001 terrorist attacks transformed the United States, the July 11 bombings have shaken Uganda to its roots.