Five people have reportedly died in western Moscow after a passenger bus drove into a crowded pedestrian underpass Monday afternoon.

Images and videos posted on social media showed a bus with blown-out windows at the stairs near Slavyansky Bulvar metro station.

The state-run RIA Novosti news agency cites a source in the emergency services as saying that five people died in the incident and 15 people have been injured.

The source told the agency that the deadly crash may have been caused by brake failure. Online video footage depicts the bus taking off after standing idle at the bus station.



The driver has been detained and taken to a police precinct for further questioning, an emergency source told RIA.



The state-run TASS news agency later cited a source in the security forces as saying that the incident was not the result of a terrorist attack.



"The possibility that this was a terrorist attack has been ruled out. The driver lost control of the wheel," the source said.