Six street cleaners were injured in a small explosion at an anti-government protest site on February 10 in Bangkok, police said.

The explosion was caused by an improvised bomb or firecracker that exploded at about 11.30am when the cleaners from the city hall were changing plant pots at a park near an anti-government rally area, according to police authorities.

Two of the workers were seriously wounded and hospitalised.

On the same day, hundreds of Thai famers joined the mass protest outside the Ministry of Justice to demand that the government quickly pay them for paddies pledged under the national rice subsidy programme.

The farm protesters marched toward to the Defence Ministry headquarters where Caretaker Prime Minister Yingluck Shinawatra and her cabinet officials are working.

Meanwhile, national security forces have been strengthened to cope with mass rallies, Lt. Gen Paradorn Pattanathabutr, secretary general of Thailand’s National Security Council (NSC), confirmed.

The subsidy programme allows farmers to sell rice to the government at 500 USD per tonne, two times higher than the market price. The government’s payment, however, has been suspended since late last month due to the dismissal of the parliament in December 2013.-VNA