They have to adjust their strategy as fewer and fewer people are coming to join the rallies, he said.
The Chaeng Wattana rally site became the latest target last night when unknown men fired the grenades into the crowds, most of whom were sleeping. However the grenades landed near a medical tent and a toilet and no one was injured.
One of the strategies would see rally leader Suthep Thaugsuban lead a march through Bangkok streets to encourage people to join the rallies, Paradorn said.
A decreasing number of people participating in the activities since the Centre for Maintaining Peace and Order cut financial support to the protests by summoning groups or companies suspected of funding them for questioning..