A man suspected of a double-murder had a confrontation with his ex-partner in a shisha bar hours before he allegedly stabbed her and her mother to death, the BBC understands.
Staff at the Rotana Shisha in Highgate, Birmingham, said they had to escort Janbaz Tarin off the premises.
Mr Tarin, 21, was also alleged by staff to have slapped Raneem Oudeh.
Ms Oudeh, 22, and Khaola Saleem, 49, were stabbed in Solihull on Monday as Ms Oudeh was on the phone to police.
Police officers were taking witness statements from workers at the bar on Thursday afternoon.
The BBC was told Mr Tarin "flew into the bar in a fit of rage" and had to be escorted out by staff.
On Wednesday, the independent charity Crimestoppers put up a £5,000 reward for information leading to his arrest.
Ms Oudeh was Mr Tarin's ex-partner and had made a number of calls to police on the day of her death.
The two women were found in Northdown Road outside their home shortly after 00:30 BST and were confirmed dead at the scene.
Detectives have said they believe Mr Tarin is still in the West Midlands area and that people are protecting him.
In a video released by the force, Det Supt Mark Payne appealed directly to the suspect.
"If Mr Tarin is watching this, hand yourself in. We will find you," he said.
The Independent Office for Police Conduct is investigating the circumstances of contact between police and the victims after the force referred itself.
West Midlands Police said there had been "a sequence of calls" from Ms Oudeh, who has a two-year-old son, in the hours before she and her mother were killed.
Mr Tarin - an Afghan national who arrived in the UK on Christmas Day in 2012 - was previously in a relationship with Ms Oudeh but is not the father of her son.