LONDON (Reuters) - British police arrested a man on Tuesday after offensive tweets were sent to British diver Tom Daley when he failed to win a medal in his first event at the London Olympics.

The Olympic poster boy and his partner Pete Waterfield were in with a chance of clinching the host nation's first gold of the Games in the synchronized 10-metre platform event on Monday, but fluffed their fourth dive and wound up just outside the medals.

Daley, whose father Robert died from cancer last year, repeated a tweet from user @Rileyy_69 to his followers that said: "you let your dad down i hope you know that".

The diver responded: "After giving it my all ... you get idiot's sending me this."

The user later apologized.

"A 17-year-old man was arrested by Dorset Police officers in the early hours of this morning, Tuesday, at a guest house in the Weymouth area on suspicion of malicious communication," police said in a statement.

"He is currently helping police with their enquiries."

(Writing by Tony Jimenez and Matt Falloon; Editing by Kevin Liffey)