The head of Network Rail made a "full and unreserved apology" yesterday to families bereaved by level crossing accidents after MPs made a scathing attack on the firm.

House of Commons transport committee chair Louise Ellman said Network Rail had shown "a callous disregard" for families suffering from level crossing accidents.

A report by the committee highlighted the treatment of the families of Olivia Bazlinton, 14, and Charlotte Thompson, 13, who were killed at Elsenham crossing in Essex in December 2005.

It said that Olivia's father Chris Bazlinton described Network Rail's failure to produce key documents during the inquest into his daughter's death as a "conspiracy of silence."

Network Rail chief Mark Carne said: "I wish to extend a full and unreserved apology on behalf of Network Rail to all those whose life has been touched by a failing, however large or small, made by this company in managing public safety at level crossings and in failing to deal sensitively with the families affected."

He said that the firm's guilty plea in the Elsenham case had been "a watershed in the way we thought about our approach to the risk at level crossings, and how we treat victims and their families."

The transport committee's report, which had called for an apology, said that hundreds of level crossings could be exceeding official death-risk limits.

It added that rail regulators should set a target of zero deaths at level crossings from 2020 and that all nine deaths at crossings in 2012/13 were tragedies which could have been averted.

The committee said pointedly that it would be "very concerned" if Network Rail executives received bonuses this year, given the company was recently held responsible for a 2010 incident at Beccles in Suffolk in which a 10-year-old boy suffered life-changing injuries.

TSSA rail union leader Manuel Cortes said bonuses should be cancelled and Network Rail "should be ashamed" of its treatment of the Elsenham families.

Transport union RMT leader Bob Crow said: "Every single level crossing presents a risk to life for both the public and rail staff and any political pressure that helps send this 19th-century solution into the history books where it belongs is welcome."