Thousand Oaks: In the aftermath of the shooting at a country music bar in southern California, in which 13 people were killed, survivors are starting to tell their stories of how they escaped through a window with the help of a fast-acting bar patron.

The bloodshed spread throughout the Borderline Bar & Grill, a popular nightspot in Thousand Oaks, an affluent city near Los Angeles.

Matt Wennerstrom talks to reporters outside the Borderline Bar & Grill in Thousand Oaks, California. Credit:Mike Nelson/EPA-EFE via The Washington Post

Customer Matt Wennerstrom, 20, described the shooter as a "tall figure", more than 1.8 metres, wearing "all dark clothing".

He said he saw the gunman open fire on employees working at the front of the bar.