Queen performed in London's Hyde Park, giving away 6,000 free tickets for emergency workers in tribute to their handling of last week's bombings.
Paul Rodgers replaces Freddie Mercury on vocals
The band allocated the tickets to London emergency services staff after their concert at the capital was postponed after the bombings.
Tickets were handed out at London's Dominion Theatre and Capital FM headquarters in Leicester Square.
Comic Peter Kay joined Queen at the 85,000-capacity venue.
Rock band Razorlight performed but Darkness members Justin and Dan Hawkins, who were due to take the stage, were unable to make the concert after its dates were rearranged.
It was the first time Queen had performed in Hyde Park for 29 years, with original singer Freddie Mercury now replaced by Paul Rodgers.
The band said they wanted the rescheduled date to become a tribute to the emergency workers.
"We feel it is fitting to thank London's emergency services for their extraordinary response in dealing with the effects of the bombing attacks and to indeed celebrate the historical resilience of Londoners in their response to yet another atrocity," they said in a statement.