JAKARTA, Aug. 5 (Xinhua) -- A 7.0-magnitude earthquake jolted Lombok Island in central Indonesia on Sunday, triggering a tsunami warning, officials said.

The earthquake was initially measured at 6.8 magnitude, but it was later revised up to 7.0 scale, Yusuf Khaidar Ali at the meteorology and geophysics agency said.

The quake struck at 18:46 p.m. local time (1146 GMT) with an epicenter 18 km northwest of Lombok Timur in West Nusa Tenggara province and a depth of 15 km, he said.

"Although the epicenter is on land, it was on the coastline and could still trigger tsunami. Accordingly we issue a warning for tsunami," Ali told Xinhua.

A small tsunami of 0.1 meter high has been detected in Carik, but the official said the tsunami warning remained in place, which indicated the possibility of further waves triggered by the quake.

At least nine aftershocks with the strongest magnitude of 4.9 followed the main shock, he added.

The temblor was felt strongly by nearby Bali resort island with V and IV MMI (modified magnitude intensity), and East Java province with III MMI, according to him.

Spokesman of the national disaster management agency Sutopo Purwo Nugroho said risks assessment was being undertaken and he predicted that many buildings, particularly the old ones in Mataram, the provincial capital of West Nusa Tenggara, were damaged.

People were advised to stay away from the coastline before the tsunami warning was lifted, he added.