A construction firm involved in the demolition of the former Deutsche Bank building is the same company that assured Minnesota officials a highway bridge was safe before it collapsed this summer.

The firm, URS, which stands for United Research Services, was hired to investigate the stability of the Interstate 35W bridge in Minneapolis in 2003. After finding numerous weaknesses, URS engineers told Minnesota transportation officials in January it would be able to find cracks and fix them before they became dangerous, according to news reports.

The eight-lane bridge collapsed seven months later, taking with it about 50 cars and killing at least 12 people.

San Francisco-based URS, a public company listed on the New York Stock Exchange, is one of the largest construction firms in the country. It has also been involved in the troubled demolition of the abandoned bank building that was condemned after the World Trade Center towers collapsed nearby. Two firefighters died there in a major fire August 18, and another two were injured in a separate incident a few days later, when a worker dropped a large tool from the 23rd floor.

Fire marshals worked through the weekend on two separate investigations, one into the cause of the fire and the other into the cause of the firefighters’ deaths.

So far, investigators have found that a standpipe that was supposed to provide water for fighting fires on the top floors was dismantled; that required visits by the fire department to oversee conditions at the site were stopped once the demolition began, and that a warren of debris and blocked stairwells hampered firefighter efforts.

Investigators from the Manhattan district attorney’s office, the state attorney general’s office, and the Department of Buildings, with the assistance of the city’s Department of Investigation, have started up their own probes to discover who is responsible for the problems that led up to the fire.

Already, one of the three construction firms involved in the demolition, John Galt Corp., has been taken off the job.

In October 2004, URS was brought on as a construction manager, a firm that acts like a broker for a property owner. Construction managers are usually responsible for identifying contractors, arranging contracts, and overseeing a construction project’s timeline.

A spokesman for the Lower Manhattan Development Corp. described URS’s role in the Deutsche Bank demolition as the owner’s representative at the construction site on a day-to-day basis.

Bovis Lend Lease, a large international construction firm that often works in the construction manager role, was brought on separately by the LMDC as the general contractor for the demolition work. Bovis Lend Lease oversaw the construction of the Time Warner Center and Bloomberg headquarters. It has also been blamed for a botched construction job at a jail in Ulster County, N.Y., and has presided over 11 major safety incidents in the past five years, including the two at the former Deutsche Bank building last week.

Bovis Lend Lease, in turn, brought on a subcontractor, John Galt Corp., which had no demolition experience and alleged mob ties, to do the actual deconstruction work at the Deutsche Bank building.

During the course of the demolition, which started this year, Bovis Lend Lease and John Galt Corp. were cited for 19 safety violations. All work has been stopped at the site following the second safety incident last week.

URS has 370 offices and 30,000 employees worldwide, according to its Web site. One of them, wearing a URS helmet and an orange construction vest, stood gazing up at the decrepit former bank building yesterday just beyond a perimeter of police fences. He identified himself as a URS employee, but told a reporter he could not talk about URS’s involvement at the site.

URS could not be reached by phone or e-mail for comment yesterday. It has declined to answer reporter questions about the Minneapolis bridge collapse, according to news reports. An LMDC spokesman said the agency could not immediately comment yesterday about URS’s connection to the Minnesota bridge collapse.

The collapse came after URS engineers had spent months examining weak points on the bridge, which had received a poor national rating. According to a Minneapolis Star Tribune report, the engineers found 52 beams in the bridge that were vulnerable to cracking and recommended that some be reinforced. It was determined, however, that fixing the cracks might result in damage to the bridge.

Instead, URS suggested that investigators could alternately keep an eye on the weak spots, but apparently these inspections had to stop during concrete repairs on the bridge this summer, according to reports.

On its Web site, the LMDC lists only URS in a section about the demolition contractors. According to the bios provided, most of the URS managers working on the demolition at 130 Liberty St. have about 20 years of experience in either demolition or construction work.

The site suggests URS is better known for its construction work, but notes that the company has worked on several high-profile demolition projects, including the decommissioning of the General Motors plant in Westchester County and the dismantling of a high rise at First Avenue and 45th Street in preparation for a building for the U.S. Missions to the U.N.

“URS has the in-house ability to provide the full services needed for the management of demolition and environmental remediation,” the Web site says. “Because our work methods are precise and organized there is minimal disturbance to the environment and compliance with all government regulations.”