Three people were killed by a bomb in Moscow on Wednesday after two police officers approached a man acting suspiciously near the site where a senior general was killed two days ago by a car bomb that Russia said was planted by Ukrainian intelligence.

A string of Russian military figures and high-profile supporters of the war in Ukraine have been assassinated during the nearly four-year-old conflict.

Ukrainian military intelligence has said it was responsible for a number of the attacks.

Russia’s State Investigative Committee said that when two police officers approached a man who was acting strangely, they were killed by an explosive device, adding that a third person was also killed. It did not specify who the third person was.

It said it opened criminal cases under clauses dealing with the murder of law enforcement officers and the illegal trafficking of bombs.

“There was an explosion,” Alexander, a resident who lives nearby, told Reuters television. “It was loud bang - like with the car a few days ago.”

Another resident named Roza said she was woken up by the explosion in the early hours and that the entire building appeared to shake.

Unofficial Russian Telegram news channels said the bomber was one of those killed and that he detonated the bomb when approached by the officers. Reuters could not independently confirm those details.

The blast took place very close to where Lieutenant General Fanil Sarvarov, head of the Russian General Staff’s army operational training directorate, was killed on Monday.

Russia said it suspected Ukraine was behind the killing.

There was no official comment from Ukraine.

Myrotvorets, an unofficial Ukrainian website that provides a database of people described as war criminals or traitors, updated its entry on Sarvarov to say the 56-year-old general had been “liquidated.”