A homemade bomb carried by a woman killed three people and injured at least 21 in an explosion near an upscale restaurant in central Moscow ​on Saturday evening, the authorities said.

The explosion occurred just before 2000 ​local time close to an Italian restaurant located in one ⁠of Moscow’s seven Stalin-era skyscrapers at Kudrinkskaya Square, the police said.

Russia’s Anti-Terrorism Committee said that ​an unidentified woman had tried to get into the restaurant but was stopped by ​a security guard, the state RIA news agency reported.

It said the woman, the security guard and a customer at the Balzi Rossi Italian restaurant had been killed in the ​blast that followed.

Those injured received wounds of varying seriousness, the police said.

Russia’s state ​RIA news agency released video of heavily armed law enforcement officers at the scene, which ‌had ⁠been closed off to the public.

The authorities did not name those killed or injured nor did they say who they thought might have been responsible.

More than four years into a full-scale war with Ukraine, Russia’s FSB security service said earlier ​this year that authorities would step ​up protection for ⁠high-ranking military officials after a series of assassinations and attempted killings it blamed on Kyiv.

The Kommersant daily newspaper cited its ​own sources as saying that the bomb had been intended ​to maim ⁠and kill guests who were enjoying themselves on the restaurant’s summer terrace outside.

It suggested that the bomb had been set off by someone else remotely and ⁠that the ​woman carrying it may not have known ​that it was an explosive device.

The restaurant’s website said the venue had been closed on Saturday for ​a private event.