A Tajik court has jailed 53 people for terrorism, most of them members of a group closely allied with al Qaeda, and all of them involved in a suicide car bomb attack in September 2010, it said on Monday.

Forty-three of those on trial had been identified as members of the Islamic Movement of Uzbekistan, the court said, referring to a group that wants to create an Islamic caliphate in the region and has fought alongside the Taliban in Afghanistan.

It was the largest group of people sentenced by a Tajik court after a single trial since the Central Asian state's independence from the Soviet Union 20 years ago.

Tajikistan, a mountainous Muslim republic of 7.7 million people which borders Afghanistan and China, is the poorest of the 15 former Soviet states.

President Imomali Rakhmon, who has ruled the mainly agrarian nation since 1992, has said that Arab-style revolutions are impossible in Tajikistan as its citizens would not risk a repeat of the 1992-97 civil war that killed tens of thousands.

But analysts say the authorities face a security threat from both home-grown rebels and a resurgent IMU.

The court in Tajikistan's northern Sughd region, where the 53 defendants had been on trial since July, said in a statement it had jailed five people for life and handed down terms of between eight and 30 years in jail to 48 defendants.

All those convicted were involved in a suicide attack on a police building in the regional capital Khujand on September 3, 2010, it said. An explosives-packed car rammed into the building of the organised crime department of the regional police, killing two officers and two civilians and wounding 28 people.

The court said the suicide bomber had been identified as a local resident named Akmal Karimov trained in al Qaeda camps in Afghanistan and Pakistan.

Khujand is located in the fertile but overpopulated Ferghana Valley which Tajikistan shares with other mainly Muslim ex-Soviet nations, Kyrgyzstan and Uzbekistan.

Authorities in Tajikistan jailed 158 Tajik members of banned religious groups last year, up from 37 in 2009, and, official data showed, jailed 92 in January-September this year.

Rakhmon has ordered Tajik students at foreign religious schools to return home and told his security services to tighten control over religious education and mosques in Tajikistan, which he said are often used to foment religious radicalism.

His critics say it is poverty and repression that push many young Tajiks to seek consolation in radical Islam.

(Writing by Dmitry Solovyov; Editing by Tim Pearce)