A Thai soldier stands guard as police officers investigate the lobby of Phramongkutklao Hospital, a military-owned hospital that is also open to civilians, in Bangkok after a bomb wounded more than 20 people, in Bangkok Monday, May 22, 2017.
Sakchai Lalit—AP
Updated: May 22, 2017 8:14 AM ET | Originally published: May 22, 2017 4:00 AM EDT

About 20 people were injured after an explosion at a hospital in central Bangkok Monday morning, the English-language online arm of Thai Khaosod reports.

Speaking with local reporters, Thailand’s deputy police chief Srivara Ransibrahmanakul said, “It’s confirmed to be a bomb,” adding that traces of batteries and electric wiring had been found at the scene.

The blast reportedly occurred at 11 a.m. local time in a reception room at the Royal Thai Army-affiliated Phramongkutklao Hospital, also known as King Mongkut Hospital. Police said the blast radius at the army-run hospital, which also treats civilians, was up to 9 feet.

Army chief Gen. Chalermchai Sittisart said the explosion appeared to use materials similar to those found in two earlier blasts in recent weeks, AP reports. “All of this was conducted with the goal of creating disorder to the administrative work of the government and NCPO [National Council for Peace and Order],” he said, referring to the official name of the ruling junta.

Hospital official Lt. Gen. Saroj Kiewkajee told AP that the blast wounded 21 people, and 13 were discharged soon after the explosion.

The attack coincides with the third anniversary of Thailand’s most recent coup d’etat, which put the current military junta in power. At least six explosions have occurred in Thailand’s capital since the 2014 coup.

[Khaosod, Associated Press]

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