The Transportation Safety Board of Canada (TSB) is sounding the alarm on a number of reported incidents at the south Ottawa railway crossing where six people died last fall.

The TSB has issued a safety warning to the City of Ottawa as part of their investigation into the fatal crash involving an OC Transpo bus and a VIA Rail train on Sept. 18, 2013.

TSB investigators found that several buses drove through the the crossing where the crash happened when safety lights were still flashing.

These incidents happened after the fatal collision.

The TSB found in three seperate incidents in October, OC Transpo buses proceeded through the railway crossing when the lights and bells were activated.

It also found in January, an OC Transpo bus went through the crossing while the lights and bells were activated, running nearly half an hour behind schedule.

In all cases, the drivers believed they could not safely stop without putting passengers at risk.

On Feb. 11, the TSB investigated another incident, this one involving three OC Transpo buses.

The TSB found one of the gates stayed down, with the lights remaining active after the passage of a train. The south gate became jammed because of frost. As a result, the gate stayed down and the lights and bells remained active until the system recovered about 10 minutes later.

While the crossing protection was still activated, three OC Transpo buses went through the crossing -- and an OC Transpo supervisor tried to manually lift the gate.

The TSB is recommending OC Transpo and VIA Rail work together to come up with safety procedures for unusual cases or malfunctions at railway crossings.

The findings are part of a TSB investigation on the Sept. 18 tragedy, when a double decker OC Transpo bus collided with a Via Train heading from Ottawa to Toronto. 5 passengers on the bus died, along with the bus driver.

In a letter to city council members today, City Manager Kent Kirkpatrick said the City of Ottawa has implemented several safety measures after the Fallowfield collision.

Kirkpatrick says City staff are now reviewing the bylaw that governs busses on the transitway.  Right now OC Transpo busses do not stop at all railway crossings, because they’re not required to.

Kirkpatrick also says the city may install earlier warnings for bus drivers, and lower speed limits on the transitway.