London police were hunting for a man who parachuted off The Shard, western Europe's tallest skyscraper, then scarpered from the scene Saturday.
The daredevil vanished following his dramatic jump from the 310-metre (1,000-feet) high glass-clad building.
Video footage of the man's descent later circulated on social media.
"I saw him making his way down between the buildings and land, and then pack up his chute and bolt," said Justin Knock, 41, who works nearby.
"Someone was there and gave him a bit of a hand to pull his chute in." He said the mystery jumper ran off towards the nearest Underground train station.
"A pretty daring bloke, who obviously knew what he was doing, and I imagine so far he's gotten away with it," Knock added.
A spokeswoman for The Shard said: "We can confirm that we are investigating an incident involving a member of the public this morning. All parts of the building remain open." A police spokesman said they were called at about 10:20 am to reports that a man had parachuted off The Shard.
No arrests have been made so far.