Police have apologised to an 11-year-old girl who had to wait 13 hours for officers to visit her after she was sexually assaulted.
The attack happened in a block of flats near the seafront in Hove at about 1800 BST on Sunday.
A friend's mother dialed 999 after the girl reached the safety of her flat - but no-one went to question the girl until the next day.
Senior officers in Sussex Police apologised after learning the girl had stayed up all night waiting to speak to them.
A police spokeswoman said officers had searched for the offender for 40 minutes without success but no-one had been available to go immediately to the victim.
Followed to flats
The girl first noticed the man when he made comments and began touching her while she queued for an ice cream.
She and a friend walked off to another part of the beach but were followed 30 minutes later as they walked to the block of flats where the friend lived.
The attacker chased the 11-year-old into a lift after the pair had been buzzed into the building, touching and pinching her.
The girl managed to escape when the lift stopped at the next floor and ran up two flights of stairs to the safety of her friend's flat.
The man is described as about 6ft tall, with dark hair and a beard and carried an electric blue motorcycle helmet.
The Sussex Police spokeswoman said they accepted in hindsight it would have been better to send some of those searching to speak to the girl.
She said police were treating the attack very seriously and were investigating a possible connection between the man and a 'mods and rockers' reunion in Brighton.