Dimla thana police seized three boring machines from the river in the last three days.

Some of the machines have been removed by their owners but some others, owned by local influentials, are still there.

"They (the influentials) are waiting to see what happens", one person who operated a boring machine told this correspondent during a visit yesterday.

This correspondent saw several hundred boring machines extracting rock and sand from the shores and areas along the embankments. They are boring up to a depth of 100 feet, making the embankments and the barrage vulnerable.

The Daily Star on Thursday published a report on the illegal extraction and its effect on the barrage.

Any sort of digging within 500 yards of embankment is prohibited, according to Dalia Division Executive Engineer of Water Development Board (WDB) Zahirul Islam. He said soil structure has become weaker following extraction of rock and sand for long.

There were problems in opening of one of sluice gates of the Barrage in the last rainy season due to formation of underwater shoal following extraction of stone and sand.

WDB officials told this correspondent yesterday that drastic and decisive actions should be taken to totally stop the illegal extraction, which began in 1997. Otherwise the Teesta Barrage, a key point installation, will face threat.

But the job will not be easy as extractors are local influentials linked with political parties, other sources in the area said.

They utilise labourers to keep the illegal activity going on. Whenever any action is taken, they instigate the labourers, who become unruly.

At the behest of extractors, several thousand labourers on Tuesday last held a rally and brought out a procession. They tried to forcibly enter the WDB office premises but were somehow controlled by some labour leaders.

Some Ansar personnel on duty at Gate No 5 near a dam close to the Teesta Barrage were attacked by some men allegedly engaged by extractors as they tried to stop stone carrying trucks.

Extraction of rocks and sand by using boring machines started after the area was leased in 1997.

Mentionably, the NSI (National Security Intelligence) after a probe into the illegal extraction termed it a "sabotage" and suggested an immediate halt to it.