BANGKOK (AFP) - Four Thai men arrested for their alleged involvement in two small bombings in Bangkok say they were tortured in military custody, their lawyer said on Thursday.
They are among more than a dozen people who have been arrested in the last two weeks - accused of planning and carrying out the attacks in junta-ruled Thailand.
"(One) man was electrocuted on his abdomen and his thigh while the other three men had their chests stomped on and were punched and slapped in the head," said Anon Nampa from Thai Lawyers for Human Rights, a local rights organisation representing the men.
Many of those detained have also been accused of having links to the opposition Red Shirt movement loyal to ousted premiers Thaksin and Yingluck Shinawatra - something the group has vehemently denied.
On March 7 a hand grenade was thrown into the car park of Bangkok's Criminal Court while in early February a twin pipe bomb exploded outside a busy shopping centre wounding two people.
The four men have all been charged with attempted murder and weapon possession.
Anon told AFP that one of his colleagues met one of the accused, Sansern Sriounruen, who described being given electric shocks during his interrogation and showed angry bruises on his abdomen and thigh.
A junta spokesman rejected claims that the men had been mistreated.
"We are confident that there is no reason for the authorities to use force or threats," Colonel Winthai Suvaree said.
Among those arrested for their alleged involvement in the attacks is nurse Natthatida Meewangpla, a prominent witness to a bloody 2010 crackdown by the military against Red Shirt protesters, in which at least 90 were killed, including a different nurse and two foreign journalists.
The 37-year-old went missing for six days after she was taken by soldiers from her home on March 11. She only reappeared publicly when she was handed over to police custody Tuesday.
Her lawyer Winyat Chatmontree told AFP that military interrogators threatened Natthatida with lese majeste charges unless she cooperated with them.
Under the royal defamation law - one of the world's strictest - anyone convicted of insulting the king, queen, heir or regent faces up to 15 years in prison on each count.
Rights groups say basic freedoms have fallen off a cliff since last May's military takeover, following the ousting of Yingluck's democratically elected government, and that draconian lese majeste legislation is increasingly being used as a tool to stifle political opposition.
Under martial law, political gatherings of more than five people are banned, criticism of the junta is outlawed and civilians can be tried in military courts for national security or lese majeste offences.
On Tuesday two men were handed five-month jail sentences for their alleged involvement in the recent grenade attack.