At least 20 members of the Turkmenistan's security forces have reportedly been killed in clashes in the capital Ashgabat, according to to media reports and diplomatic sources.
Police battled "a religious group, possibly radical Islamists", according to a diplomatic source quoted by a website set up by
Boris Shikhmuradov, founder of Turkmenistan's opposition Popular Democratic Movement.
"Witnesses said that 20 police were killed and their bodies were taken in secret to an Ashkhabad hospital," the www.gundogar.org website, which is not accessible in Turkmenistan, reported on Saturday.
Information is strictly controlled in the former Soviet republic and state media did not report on the incident.
The reports of clashes could not be independently confirmed but witnnesses told news agencies that there was heavy gunfire throughout the night and the northern suburbs of the capital were surrounded by police.
Other witnesses said that security personnel in armoured personnel carriers were patrolling the streets which remained closed for much of Saturday.
Arkady Dubnov, a Moscow-based reporter for the Vremya Novostei newspaper and expert on Central Asia, told the AFP news agency that sources in Ashgabat had told him of "tanks and armoured vehicles opening fire on a drinking water factory" where an armed group was hiding.
The US embassy in Turkmenistan warned Americans to stay away from the northern districts of the city.
The Central Asian nation, bordering Iran and Afghanistan, has a predominantly Muslim population and large oil and gas reserves.
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