Colombo - At least 52 Tamil rebels and 15 government soldiers were killed after heavy fighting erupted in northern Sri Lanka Wednesday as security forces launched a fresh offensive to recapture rebel-held areas, military sources said.

Another 72 government soldiers were reported wounded in the clashes.

Earlier the Defence ministry said troops had launched a fresh offensive on two rebel strongholds located in Muhamalai and Kilaly, 390 kilometres north of the capital, on Wednesday morning.

The two areas are located in the southern part of the northern Jaffna peninsula where more than 400,000 civilians live. The fighting was along the boarder of the military controlled areas.

Security forces started their advance in the early hours of Wednesday and claimed they captured the Tamil rebels' first line of defence.

"Monitored radio communications and ground sources have confirmed that LTTE (rebels of the Liberation Tigers of Tamil Eelam) has suffered heavy casualties," the Defence Ministry said in a statement.

A pro-rebel website also confirmed that heavy fighting was taking place in the two areas.

"LTTE defensive formations were confronting the Sri Lanka Army units that have mounted offensive attacks simultaneously at several locations around 3:30 am," the Tamilnet website said.

Heavy artillery barrages were reported in the northern front, the report said.

On Tuesday the military claimed they destroyed nine rebel bunkers in Muhamalai and in the process seven soldiers were wounded.

Elsewhere in the north on Tuesday, at least nine rebels were killed.

Government troops have been carrying out military operations from several fronts in the north-west, north-east and the central part of the north during the past four months. At least 2,500 rebels and more than 300 security personnel have been killed during the period in the north. (dpa)