A property developer and his son were stabbed to death in a knife attack at his family-run firm's office.
Terry McMillan, 58, and his rugby player son Brendan, 27, were identified as the victims of the quadruple stabbing at an office near London Bridge on Monday.
A third man, in his 30s, is recovering in hospital. A suspect, 31, is also in hospital under police guard after being arrested on suspicion of murder.
The group were attacked at the office of The Trademark Group, their property development and investment company based at 197 Long Lane in Bermondsey.
Terry was pronounced dead at the scene while University of Gloucestershire graduate Brendan was taken to hospital where he later passed away.
Witnesses said they heard someone screaming 'Help me!' and later paramedics were observed carrying out CPR on a stretcher-bound man, The Telegraph reported.
“I saw him [the suspect] get tackled to the ground,” a witness said.
“There were 12 to 15 people out the back. There was a load of commotion, hundreds of people looking out from the balconies. He was on the ground, facing down, shirtless. He was quite bloody.”
One of Brendan's former rugby clubs today paid a heartbreaking tribute to the late sportsman on social media.
“Yesterday, Old Colfeians lost a member of our family, one of the kindest, funniest, most genuine people you could ever meet,” the post said, alongside a reel of photos of Brendan on and off the pitch.
Brendan lit up every room he walked into, forever smiling, always cracking a joke and always full of life.
“His absence will be deeply felt for a long time to come. We will miss him more than words can say and we'll always carry his memory with us.
“We are also mourning the loss of his beloved father, Terry, a long time supporter and sponsor of the club.
“Our thoughts and prayers are with their family and friends during this incredibly difficult time. Rest in peace, Brendan McMillan. Rest in peace, Terry McMillan.”
A local MP said the men were killed in a ‘targeted attack’.
Labour MP Neil Coyle, who represents Bermondsey and Old Southwark, told reporters outside the police cordon on Tuesday: "This is truly awful.
"It's absolutely devastating for the family and the local community.
"Thankfully, police say this was an isolated incident.
"The man who carried out the attack knew the others involved.
"There's no excuse for what happened, but there's no further risk to the public.
"Police believe they have witnesses, but if anyone else saw anything, please contact the police and share any information you have.
"Lots of people will be shaken.
"As the local MP, I want to send my condolences to the family and everyone directly affected.
"But this is a safe community.
"This was a targeted, isolated incident.
"The man responsible is already detained, and as you can see, police are investigating thoroughly.
"Paramedics also did everything they could yesterday to try to save lives."
Mr Coyle also pleaded with witnesses to come forward.
He added: "My message to the community is this: if you saw anything, please come forward.
"And if you didn't, but you're worried, know that this remains a safe area.
"The person responsible has been detained and there is no ongoing threat to public safety.
"I'm working closely with police and the local council.
"The investigation is ongoing, but when more information can be shared, it will be.
"My job is to make sure my constituents are kept informed and reassured that there's no wider risk."
A resident, who asked not to be named, said: "It's terrifying.
"I walk past there all the time – it makes you feel really uneasy.
"You just don't expect something like this to happen on a normal weekday."
Detectives from the Metropolitan Police's Specialist Crime Command are leading the investigation.
