WASHINGTON - The US Secret Service failed to replace a broken alarm system at the Houston home of former President George HW Bush for more than a year, according to a government report on the troubled protection agency.

The report, which was sent to Secret Service Director Joseph Clancy and released on Thursday, was compiled by the Department of Homeland Security’s inspector general, John Roth, who said the agency now will improve its process for tracking maintenance problems with security equipment and keeping it up to date.

The 20-year-old alarm system at Bush’s home stopped working in September 2013 and was not replaced until November or December in 2014.

The report said the agency had been warned in 2010 that the alarm was likely to fail but a request to have it replaced was rejected.

The DHS said a Secret Service employee was assigned to roam the property while the system was broken and no security problems occurred.

The report said similar vulnerabilities could be affecting residences of other former presidents.

Roth’s report is part of an overview of security breaches, including a man with a knife who jumped the fence and entered the White House last year and another man who fired shots at the presidential residence in 2011.

Roth’s office also is looking into incidents in which Secret Service supervisors drove their government vehicle into an investigation scene at the White House after a party and allegations of sexual assault and improper use of the agency’s data base by employees.

Julia Pierson resigned as director of the Secret Service in October a few weeks after the White House intruder incident. The agency’s credibility also has been tarnished by revelations about agents hiring prostitutes while on assignment in Colombia in 2012.