BISHKEK, Kyrgyzstan - A magnitude-6 earthquake rattled southern Kyrgyzstan on Monday night, causing cracks in houses but no casualties, the second quake to shake the Central Asian country in two weeks, authorities said Tuesday.

The quake that struck settlements in Batken region around midnight centred in an area 90 kilometres southwest of the regional centre near the border with Tajikistan, the Emergencies Ministry said.

It said emergency services were working in the area to assess the damage and provide assistance to the local population.

Authorities in neighbouring Uzbekistan said that tremors measuring five on the Richter scale were registered in the capital Tashkent on Monday night.

Two weeks ago, an earthquake of a magnitude of 5.5 struck northern Kyrgyzstan causing cracks in thousands of houses but no casualties.

Mountains cover about 90 per cent of the poor ex-Soviet republic.