A bomb attack at a military-owned hospital in Bangkok injured at least 42 people on Monday, March 22.

The army chief, Gen. Chalermchai Sitthisart said 18 people were hospitalized after the explosion struck a reception room for retired civil servants at the Phramongkutklao Hospital at about 11am.

The attack is believed to be connected to two recent pipe bomb explosions on Ratchadamnoen Avenue, each of which injured two people, the general said.

“All three incidents happened in public spaces, and we believe they all were done by the same perpetrators,” he said.

However Monday’s bombing was an escalation, Chalermchai added, as it seemed intended to inflict mass casualties.

No suspects have been identified yet but investigators are reviewing security cameras at this time, he said.

Deputy police commissioner Srivara Ransibrahmanakul said earlier today that evidence of a bomb device was found at the scene.

“It’s confirmed to be a bomb,” Gen. Srivara told reporters. “We must convene a meeting before saying anything further, but at this time, I can confirm it was a bomb.”

Traces of a batteries and electric wiring were found, the deputy police chief said. It was also the first of the three such bombs packed with shrapnel to increase casualties, he said.

The hospital is located on Ratchawithi Road near the Victory Monument. The reception room is named after the Wongsuwan family, which counts several high-ranking military officials including current Defense Minister and junta deputy leader Prawit Wongsuwan.

The army has taken control of the investigation. Col. Preecha Saomuang of Phaya Thai police said soldiers have sealed off the crime scene, and police officers are not being allowed into the area.

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