Kenyan police said they were holding a dozen people today over the twin bomb and missile attacks on Israeli tourists, after Israel vowed to hunt down all those behind the Mombasa attacks.
Police said an American woman, a Spanish man as well as six Pakistanis and four Somalis were being held in connection with the attacks.
Earlier it was confirmed a man and woman detained in connection with today's attacks had used US passports and said they were from Florida, the manager of a hotel where they stayed told reporters.
Police said they were hunting others of Arab appearance.
Suicide bombers drove a car into the lobby of the Israeli-owned Mombasa Paradise beach hotel and blew it up, killing 15 people, minutes after missiles were fired at a plane full of Israeli tourists taking off nearby early yesterday.
Al-Qaeda remained prime targets of suspicion. There was no publicised evidence against the network, but analysts said the synchronised raids were a hallmark of al-Qaeda's operations and speculated that as its first direct attacks on Israelis, they were intended to rally Muslim support.
Today, 12 people were being held. "Only one among those held is a Kenyan. Eleven are non-Kenyan," a police spokesman told reporters.
Police Commissioner Mr Philemon Abong'o told a news conference earlier: "We feel that some of them have information which could be useful to us." He declined to give the nationalities of those held.
Mr Ben Wafula, manager of Mombasa's Le Soleil Beach Club, said of the first two detained: "They had American passports and they said they were from Florida." He said the "Italian or Spanish" looking man and the blonde woman checked into his hotel on November 26th and had tried to check out on Thursday morning, about two hours after the suicide bombing of the Paradise Hotel some five km (three miles) away.
Mr Wafula said the pair were detained after his staff made a routine call to police, who had asked all hotels in the area to notify them of any people checking out following the blast. The couple had phoned Spain soon after the bomb blast, he added.
Israeli and US experts pored over the wreckage of the Paradise and the suicide bombers' car.
"A Pajero passed the hotel gates then after a few minutes came back and passed the gate again. On the third trip it came and swerved into the hotel," said the hotel security guard.
Israeli survivors were flown home in an Israeli air force plane which also brought back the bodies of the three Israelis killed, two brothers aged 13 and 15, and a 61-year-old man.
Among the other victims were Kenyan dancers who had been welcoming tourists in the hotel lobby when the bomb went off.
"Terrorism is dangerous, not only to Europe and the United States, but also to Africa, and we must fight it," Kenyan President Mr Daniel arap Moi said as he inspected the ruins. Mombasa is a mostly Muslim city with links to the Arab world. Prominent Islamist Abubakar Awadh, an official of the Supreme Council of Kenya Muslims, said today: "If this was done to Israelis alone, it would be a worthy cause." He said he was speaking in a personal capacity.
Israeli and Kenyan officials have been quick to blame Osama bin Laden's al-Qaeda network. But the White House said it was too soon to blame the group it accuses of mounting the September 11th attacks.