Jennifer Weist, lead singer of punk rock group Jennifer Rostock, was out with friends in Friedrichshain club Astra on the night of Saturday 15th August.
As she left for home with a friend, the two were approached by two teens. The pair tried to rob them, before turing on Weist's friend with a knife.
The violent assault gained public attention across Germany. And in the early hours of Sunday morning, police arrested a 15-year-old boy in connection with the attack.
'He would have died there in my arms'
Weist spoke of the attack in a Facebook post the following Monday, urging others to take care when visiting the Warschauer Straße and RAW-Gelände area.
"Two young boys tried to take my wallet out of my waistbag," she wrote.
Her friend tried to push the boys away,she said - yet three others soon approached from across the street.
"I called out for help, and two guys came over and tried to help, but it was too late," Weis continued. "One of the boys took out a knife."
The boy slashed Weist's friend across the throat.
"All of his arteries were exposed," she wrote. "Just a few milimetres further and he would have died there on the street in my arms. I thank God that didn't happen."
ich war am samstag mit freunden im astra in friedrichshain. als ich mit einem freund nach hause gehen wollte, versuchten...
Posted by Jennifer Weist on Monday, 17 August 2015
Police make arrests
Police presence in the area was increased after the assault - and on Monday, police said in a statement that they had arrested a 15-year-old in connection with the attack.
The teen was arrested along with a 17-year-old in the nearby Warschauer Straße U-Bahn station.
The two were spotted by passers-by at around 3am, as they tried to rob a sleeping woman in the station, reported BZ on Monday.
Witnesses alerted police, and the duo were arrested soon after.
The teen fought with officers as they tried to detain him, and injured one officer in the knee.
He was identified as one of the attackers from the previous Sunday, and will now face criminal charges.
Police are still searching for the second man in connection with the attack.
A dangerous party hotspot?
The RAW-Gelände, home to many of Friedrichshain's famed clubs and bars, is a popular party spot for tourists.
Yet the former East German railway maintenance yard is also becoming notorious for the number of thefts and drug crimes, reports DPA.
"Be careful when visiting the RAW area," warned Weist in her Facebook post.
She urged visitors to be cautious about walking alone in the area at night, adding "these people are insanely dangerous."
By Hannah Butler