A high-ranking manager who oversees internal fraud investigations at the Canada Revenue Agency was assaulted overnight Friday as he left a staff Christmas party in Montreal.

'I can't comment on the specific employees, but we'll make sure they're safe at all times.'—Canada Revenue Agency Minister Keith Ashfield

The 55-year old CRA manager was attacked in a parking lot in Montreal's Little Italy just after midnight, after attending a work party earlier in the evening.

The man works for the agency's Montreal office, where he heads an internal tax evasion investigation.

Police said one or several suspects punched him in the face and kicked him on the ground before fleeing.

The victim suffered some lacerations, but didn't require hospital care.

Police said they are searching for one or several suspects.

Assault follows revealing media report

The attack came hours after CBC's French-language service broadcast an exclusive report about an administrative investigation that singled out nine employees at the revenue agency in the last 18 months.

Nine employees at Canada Revenue's Montreal office were singled out in an internal tax evasion probe. (Radio-Canada)

According to Radio-Canada's investigative program Enquête, six of those workers have been fired since the administrative probe was launched in the spring of 2009.

The victim was appointed to lead the agency investigation after a major round of raids in April 2009 targeted several Montreal construction companies suspected in a tax fraud scam worth $4.5 million.

The companies included Simard-Beaudry Construction Inc. and Construction Louisbourg Ltd., both accused of funneling almost $4.5 million to two dummy corporations used in a false invoicing scheme.

Quebec construction magnate Tony Accurso was linked to both companies.

Last week, Simard-Beaudry and Louisbourg Construction pleaded guilty to the tax evasion charges, and now must pay a combined $8 million in fines and back taxes.

The guilty plea may affect Montreal's future super-hospital, which is currently being built in the city's west-end Glen Yards. A consortium of companies, including Simard-Beaudry, is collaborating on the McGill University Health Centre superhospital.

The guilty tax evasion plea means the company may face sanctions that could affect its operating licence. Quebec's provincial building-code authority — the Régie du batiment — is currently investigating.

Assault raised in question period

Opposition MPs are demanding more details about the internal revenue investigation.

"How many bureaucrats are targeted in this probe, and how many construction companies profited from this system in which one could buy the co-operation of Canada Revenue workers?" asked Bloc Québécois MP Robert Carrier, during question period Monday.

"I can't comment on the specific employees," responded Revenue Minister Keith Ashfield. "But we'll make sure they're safe at all times."

With files from Alain Gravel