ALMATY, May 8 (Reuters) - An Uzbek prisoner who died while serving a 15-year sentence on charges of religious extremism had violent marks on his body indicating injuries from torture, his father said on Thursday.

Uzbekistan's government is accused in the West of tolerating no dissent and allowing the use of torture in jails. President Islam Karimov, in power since 1989, has denied the allegations.

Odil Azizov, 25, died on May 4 in a prison hospital in the capital Tashkent where he had been moved from the Zhaslyk prison, his father said. Rights groups say Uzbekistan keeps most its political prisoners at Zhaslyk in a remote western desert.

Reuters could not reach justice officials for comment on Thursday despite repeated attempts.

Azizov's father told Reuters his son's body was covered with signs of torture when it was handed over to him on Monday.

"I saw a large stain and bruises on the left side of his chest. ... His feet were swollen," Makhmud Azizov said by telephone from the eastern city of Kokand where he lives.

"When he was dying I appealed to all government bodies for urgent surgical treatment but nothing was done. ... They (prison officials) were just waiting for his death," he said, adding his son had complained of mistreatment while serving his term.

Azizov was jailed in 2001 after a court charged him with crimes that included violation of the constitution, membership of an Islamic organisation branded as terrorist by the Uzbek government, and distribution of illegal religious books.

In a November 2007 report, the United Nations accused Uzbek police and prison staff of "routine use of torture" to extract confessions. The Uzbek government denies the accusations.

Uzbekistan has been under pressure in the West since troops fired on protesters in the eastern town of Andizhan in May 2005. Witnesses said hundreds of protesters were killed. The government said troops fired only at Islamic extremists.

Some western nations have pointed to an improvement in the Uzbek rights situation this year after the former Soviet nation showed signs of willingness to activate contacts with the West and decided to pardon a number of prisoners.

Last month, the European Union chose to maintain its suspension of sanctions on Uzbekistan for another six months, but said they could be reapplied if human rights conditions do not improve.

Surat Ikramov, a prominent Uzbek rights defender, said the situation in prisons was dire, with at least 20 inmates dying of various causes every month.

He said another prisoner, 26-year-old Abdurakhim Tashpulatov, died in late April after telling his mother that he could die in prison because of threats from his prison wardens.

He was also serving a long sentence on charges of religious extremism, Ikramov said. Justice officials could not be reached for a comment on this case either.

"Half of them are those who die of torture. And the authorities thoroughly hide this by putting pressure on relatives," Ikramov told Reuters. "The fight is under way to annihilate these people (religious prisoners) physically". (Editing by Mary Gabriel)

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