The United States is warning its citizens they could be the target of terrorist attacks in east Africa similar to the recent twin attacks on an Israeli-owned airliner and resort hotel in Kenya.

"The Department of State believes that Djibouti is one of a number of countries in east Africa where there may be an increased terrorist threat," the U.S. State Department said in a statement.

While it said its information regarding the terrorist threat in Djibouti had yet to be verified, it warned U.S. citizens about travelling to east Africa.

The U.S. warning comes amid reports that Australia and Germany issued alerts of possible terrorist activity in Kenya at least two weeks before Thursday's missile attack and suicide bombing that left 16 people dead near Mombasa.

Meanwhile, Kenyan investigators have not ruled out the possibility of al Qaeda involvement in the attacks, Kenya's defence minister said Saturday.

Officials said Osama bin Laden's al Qaeda network has struck Kenya before -- it's blamed for the deadly 1998 attack on the U.S. Embassy in Nairobi -- and its involvement in Thursday's suicide blast in Mombasa and a missile firing at an airliner remains undetermined.

"Kenya has been attacked by al Qaeda (before), so we cannot rule them out," Internal Security and Defence Minister Julius Sunkuli told the Associated Press.

"Over the last six months, Kenyan investigators have been following certain leads, (but) not particularly on this."

Although a previously unheard of group, The Army of Palestine, has claimed responsibility for the Kenya attacks, experts say such synchronized strikes have all the hallmarks of an al Qaeda operation.

The U.S. has said that the Somali militant group Al-Ittihad al-Islamiya, linked to al Qaeda, is the prime suspect in the attacks.

Responding to that claim, Somalia's interim government said Saturday it would work to help dismantle terror groups in East Africa.

"The government feels it is time to work together as a region and international community to dismantle terror groups wherever they are," Transitional National Government (TNG) Prime Minister Hassan Abshir Farah was quoted as saying by an official.

Four Somalis were among 10 people held by Kenyan authorities on Saturday in connection with the hotel blast. Police have since released an American woman and her Spanish husband.

Kenyan President Daniel arap Moi has expressed bitterness over the return of terrorism to his country.

"We are very bitter because our economy relies upon people who come here freely," he said.

On Friday, Kenyan authorities unveiled two missile launchers they said were found near the end of the runway where the Israeli plane carrying 261 passengers narrowly missed being shot out of the sky. The plane later landed safely at Tel Aviv's Ben Gurion Airport.

There were also unconfirmed reports in the Kenyan media that witnesses saw a light plane flying over the hotel at the time of the attack, dropping clusters of small bombs.

One of three suicide attackers involved in the hotel bombing was identified as Abdullah Ahmed Abdullah -- a name that matches one of the most wanted al Qaeda terrorists sought by the FBI.

Another was identified as Faed Ali Sayam. That name also is similar to the name of a wanted al Qaeda terrorist. Both of the men were indicted in connection with the deadly 1998 twin U.S. embassy bombings in Africa that killed 224 people and injured 5,000.

Two children were among the three Israelis killed in the hotel bombing. Ten Kenyans were also killed, including a traditional African dance team welcoming tourists. More than 80 others were wounded.

Gilad Millo, a spokesperson for the Israeli Foreign Ministry, said 235 Israeli tourists, including 15 injured in the blast, flew home Friday. The bodies of the three Israelis killed in the attack were also onboard the evacuation flight.

The Department of Foreign Affairs and International Trade issued an advisory after Thursday's attacks warning Canadians to "maintain a high level of personal security awareness at all times as the security situation could deteriorate rapidly without notice."

With reports from Reuters and The Associated Press.