BISHKEK, June 11 (Xinhua) -- The death toll from overnight clashes in southern Kyrgyzstan had risen to 37, health authorities said Friday.

The death toll from the clashes in the second largest city of Osh could further rise, as many of the more than 500 wounded were in critical condition, an official from the country's Health Ministry said.

The clashes prompted the interim government to declare a state of emergency in Osh earlier on Friday. Fighting had not abated by evening and authorities imposed a curfew from 8 p.m. to 6 a.m. until June 20.

Armored vehicles were sent in to stabilize the situation after hundreds of youths smashed windows, looted shops and set fire to cars.

Servicemen drive armoured vehicles in the city of Osh in southern Kyrgyzstan June 11, 2010.

The clashes followed violence in May when supporters of former President Kurmanbek Bakiyev clashed with supporters of the interim government in the southern cities of Osh and Jalalabad.

Bakiyev was ousted in April when riots broke out across the Central Asian country. At least 85 people were killed and thousands of others injured in clashes.

Kyrgyzstan is expected to have a vote on a new constitution later this month, followed by new parliamentary elections in October.