A homemade bomb exploded outside an upscale restaurant in central Moscow on Saturday, killing at least three people and injuring 21 others.

Russian authorities said a woman carrying the explosive device was stopped by security before the bomb detonated, killing her, a security guard, and a customer.

Some media reports later claimed the death toll had risen to five, though officials had not confirmed those reports.

Investigators have not identified any suspects or established a motive, but unverified reports suggested a senior Russian military commander may have been the intended target, The Moscow Times has reported.

The attack has sparked speculation about a possible connection to the war in Ukraine, though no evidence has been publicly confirmed and Ukraine has not commented.