The Thai government's intelligence reports have discovered terrorists during Saturday's clashes have linked with the "red-shirt" core leaders, Deputy Prime Minister in charge of security affairs Suthep Thaugsuban said Tuesday.

It was found that some terrorists are the "red-shirt" guards (at the rally sites), the National News Bureau of Thailand quoted Suthep as saying.

Suthep also said the "red-shirt" core leaders knew the plans before they would be operated by the terrorists.

Hence, the Thai government is now concerned over the safety of the "red-shirt" protesters, Suthep said.

Prime Minister Abhisit Vejjajiva Monday told the nation on a live television the government is going to distinguish terrorists from the "red-shirt" protesters.

It has been obvious the terrorists used the "red-shirt" political movement as a tool to create chaos aiming for a big change, Abhisit said.

In a related development, Metropolitan Police Commander Lt- General Santhan Chayanon said police forces from Provincial Police Region 1-9 were prepared to reinforce police stationed in Bangkok.

The provincial police will participate operations to ensure security in Bangkok, he said, adding that they will reinforce at 16 check points in the inner areas of Bangkok.

Some 92 police companies consisting of 13,800 police personnel have been deployed to ensure security in Bangkok, Police Major General Piya Uthayo, the spokesman of the Metropolitan Police Bureau said Monday.

The Saturday's clashes between troops and "red-shirts" in capital Bangkok resulted in the death of 21 people and injured some 800 people.

By Tuesday some 276 people injured during the clashes were still in hospitals and some 17 of them were in intensive care units, the (Erawan's) Bangkok Emergency Medical Service Center reported.