Apr 9, 2009 (DVB), A border offensive this week against Burma's main armed opposition group is an attempt to clear the area of rebels prior to the construction of a deep-sea port and coal factory, said an opposition group member.

This is the second week of government offensives against the armed wing of the Karen National Union, the Karen National Liberation Army.

The attack on Tuesday occurred near the Thai-Burma border in Tenasserim Division, southern Burma.

"The [military] moved three of its battalions to the region about 10 days before the clash happened and the motive was to drive our battalion 203 out of the area," said a KNLA information official.

"The SPDC needed that area for their business deal with Thailand so they are trying to force us out now, and also the Thai government told us to move out from there too."

The KNLA official said that four army soldiers were killed in the offensive, while no deaths of KNLA fighters were reported.

The latest incident is the second major attack launched by the ruling State Peace and Development Council in the last two weeks.

Offensives against armed opposition groups usually occur around this time of year.

In other news, a fight broke out between KNLA troops and Democratic Karen Buddhist Army forces in Karen state's Walakee region around midday today, said KNLA Lieutenant Kyi Aung.

The incident follows an attack yesterday by DKBA troops on an outpost near a strategically important KNLA base.

"It is obvious to us that they are going to keep coming and it is our duty to drive them out with no mercy to defend ourselves," said Kyi Aung.

"We are preparing for counter attacks." The DKBA split from the KNU in 1994 and allied itself to the government.

With three Karen splinter groups now allied to government forces, some Burmese military analysts have speculated that recent attacks by Burmese troops could be due to information supplied by the defectors.

Reporting by Htet Aung Kyaw and Thurein Soe