A homemade bomb carried by a woman killed three people and injured at least 21 in ⁠an explosion near a restaurant in central Moscow on Saturday evening, prompting speculation on social media that the attack may have been linked to the war in Ukraine.

The explosion occurred just before 8pm local time (6pm UK time) close to an Italian restaurant in one of Moscow’s seven Stalin-era skyscrapers at Kudrinskaya ​Square, police said.

Russia’s anti-terrorism ‌committee said an ‌unidentified woman carrying ​an improvised explosive device 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 restaurant were killed in the blast.

REN TV cited a source on Sunday as saying that two people who had been taken to hospital had later died of their wounds, bringing the death toll to five, but there was no official confirmation. The channel said six people were in a serious condition.

Moscow’s mayor, Sergei Sobyanin, offered his condolences to the families of those killed and said those responsible would be punished. “A brutal terrorist ‌attack was carried out in Moscow yesterday,” he said in a statement on Sunday.

Heavily armed law enforcement officers sealed off the scene of the attack. The authorities did not name those killed or injured ​or any suspects. Unverified social media reports suggested a senior Russian military commander had been the intended target but had been unharmed.

More than four years into a full-scale war with Ukraine, Russia promised better protection for high-ranking military officials this year after a series of assassinations and attempted killings, which it blamed on Kyiv. Russian war bloggers, without citing any evidence, were quick to blame Ukraine for ⁠the latest attack. Kyiv did not immediately comment.

The Kommersant daily suggested the woman carrying ​the bomb may not have known about ​it, and that it had been set ​off remotely by someone else.

The restaurant’s website said the venue had been closed on Saturday for a ​private event. The nature of ‌the attack recalled a ​bombing carried out in ​2023 that killed the Russian pro-war blogger Vladlen Tatarsky. A young woman, Darya Trepova, was jailed for 27 years for delivering a bomb concealed inside a statuette that exploded in his hands. She said she had been acting under instruction from a man in Ukraine who had sent her money.

Senior Ukrainian officials at the time neither claimed responsibility nor denied involvement.