An extremist group blamed in attacks that killed 47 people earlier this year orchestrated suicide bombings Friday against the U.S. and Israeli embassies and the Uzbek chief prosecutor's office, an anti-terrorism official said Saturday.

The latest attacks, which killed three people, were retaliation for the continuing trial of 15 suspects, allegedly linked to Al Qaeda (search), in the attacks four months ago, Tashkent police anti-terrorism chief Oleg Bichenov told The Associated Press.

"It is connected to the trial and has been carried out by remnants of the same group," Bichenov said. "These are links in one chain."

The first trial for those attacks -- which hit in late March and early April -- began Monday in Uzbekistan (search)'s Supreme Court. The defendants have all pleaded guilty and said the U.S. and Israeli embassies were among planned targets for their extremist group, known as Jamoat, which means "society" in Uzbek, planned to attack.

They have said the group ran training camps in Pakistan (search) where they were taught by Arabs who the government says were Al Qaeda instructors.

The death toll from Friday's attack rose to three after a police officer who was guarding the U.S. Embassy died overnight from his wounds. There were eight wounded. The toll did not include the three suicide bombers.

Bichenov said police were taking "all necessary measures" to ensure security in the capital.

The trio of bombers struck nearly simultaneously Friday evening in the Uzbek capital, killing two Uzbek guards outside the Israeli Embassy, including the ambassador's personal bodyguard.

Interior Minister Zokirjon Almatov told Russia's ITAR-Tass news agency that authorities had detained a "group of people" on suspicion of involvement in the attacks, but gave no further details. Bichenov had said earlier that no arrests were made.

President Islam Karimov cut short a vacation and returned home Saturday to head a government commission on the bombings.

Uzbekistan, which borders Afghanistan, is a key U.S. ally in the war on terror despite the government's poor human rights record, and U.S. troops are based here.

The commander of the U.S. base in the southern city of Khanabad told AP he was monitoring the situation but there were no known threats against the facility. Security is always tight at the base, where U.S. troops keep a low-profile and aren't allowed to go outside.

"We're aware of the incidents that occurred in Tashkent and are taking appropriate steps," U.S. Army Lt. Col. Neal Kemp said Saturday.

Opposition groups have said the earlier, deadlier, attacks were motivated by anger at Karimov's repressive regime. In an attempt to stem extremism, more than 6,000 people have been jailed since the 1990s in a harsh government crackdown on Muslims who practice outside the country's state-run mosques, according to human rights groups.

Bichenov dismissed a claim of responsibility on a militant Web site for Friday's attack, saying he hadn't heard of the group. The claim from the Islamic Holy War Group was signed, "your brother in Bukhara: Mohammed al-Fatteh." Some of the defendants in the ongoing trial are from the central region of Bukhara.