Two strangers are believed to have jumped from a bridge just minutes apart from each other before police could respond and try to save them.
The men are both missing and feared dead after they disappeared just 50 metres apart from each other on the Humber Bridge near Hull.
One of the men has been named by family as Hull resident Sam Conlin, 24, while the other is believed to be a missing grandfather from Grimsby, Lincolnshire.
Sam’s father Ian Conlin told Hull Live that concerned officers watched the double tragedy unfold as they monitored his son on the bridge’s CCTV system.
He said Sam had insecurities about his appearance, but his family “will never know” why he decided to take his own life.
Mr Conlin, 55, said officers were watching Sam on the bridge in the early hours of Saturday morning when a car pulled over and a second man walked to a railing and disappeared before police could respond.
The camera was turned to the second man, and when it was turned around to look for Sam, a joiner, he was not on the bridge, his father said.
The second man is thought to be a grandfather from Grimsby who is in his 40s, Grimsby Live reported.
Mr Conlin said: “We know it was Sam on the bridge, it was definitely him because they got him on camera.
“The police were tracking him, but then another man, an older man, stopped his car further up the bridge and jumped off – and they had to deal with that.
“When they turned the camera back round, Sam was not on the bridge.”
Mr Conlin said Sam had secretly battled mental health problems for eight years, and he left a note for his family saying he did not want to live.
He added: “We will never know why Sam took his own life.
“From what he told us, he had insecurities about his appearance and the way he looked, but I could never understand why because he was a big, strong, good looking lad.
“The note, which was addressed to the family, said ‘I know it’s going to hurt you forever, but I just cannot go on any longer’.
“We only found out that he was struggling with mental health three months ago, but we never thought he was suicidal.
“He was enjoying his job, I worked with him too, he had his own house and his own car – he had no debts.
“We didn’t realise the extent of Sam’s mental health and that he was feeling suicidal.”
Sam has not been found, but Mr Conlin believes he is dead.
He added: “There is no doubt that Sam is dead after jumping from the Humber Bridge.
“Obviously, the police cannot confirm it until they find his body.”
The distraught father made a tearful plea, encouraging people to speak to someone if they are feeling suicidal or depressed.
He said: “I just want to say if other young people are reading this and feeling suicidal or depressed then speak or talk to your parents – talk to anyone. They will help you get through whatever it is you are going through.
“We just feel like Sam didn’t even give us a chance for us to help him, but it might not be too late for someone else.”
Humberside Police said a man reported missing from Grimsby was last seen on the south side of the bridge just before 4am on Saturday.
It was the same time Sam was being monitored on CCTV, his father said.
Both cases are still being treated as missing persons inquires, as no bodies have been found despite a search involving police, Humber Rescue and the Coastguard.
A police spokesman said: “Shortly before 4am on Saturday, our officers attended to a concern for safety at the south side of the Humber Bridge following reports that a man in his 40s from Grimsby had entered the water.
“Search teams were deployed to search the river and area however the man has not been located.
“The man’s next of kin has been informed and will be supported by specially-trained officers.”
For confidential support call the Samaritans on 116123 or visit a local Samaritans branch, or see samaritans.org for details.