Syracuse, NY -- Syracuse Mayor Ben Walsh can't say whether railroad bridges in the city are safe because inspection records remain hidden a day after sections of a railroad concrete wall fell on a downtown street.

Walsh said the city still needs more information to continue making informed decisions to protect the public.

Thursday evening, the mayor said he wasn't aware of any imminent threats. But he stressed today that he was still waiting for safety records that might show whether there are other possible threats from the railroad track that crosses the city.

The track -- much of it elevated -- runs 6.5 miles in Syracuse and crosses 22 streets, according to Google maps. The track and bridges were built in the 1930s, city officials said.

Each section that fell was estimated to be about 60 feet long, city officials said.

Walsh said that the investigation into what caused the concrete wall of a rail bridge to crumble into a downtown street was being handled by federal and railroad authorities. The 1:04 p.m. collapse Thursday narrowly missed several civilian vehicles and has closed South Clinton Street in the area indefinitely.

The city has not been provided with a lot of specific answers yet, the mayor indicated.

For example, the city did not know if any emergency inspections had been conducted in the past day on bridges along the railroad's other 6.5 miles right-of-way in the city.

The New York, Susquehanna & Western railroad told Syracuse.com independently that engineers are in the process of checking all "elevated structures and bridges" in the city. That's on top of weekly track inspections, which did not catch the failing concrete wall.

The city had not been told if federal authorities had conducted any independent inspections, Walsh said.

The city, while handling security on the ground, has deferred to the railroad on issues regarding the tracks. As a videographer was trying to deploy a drone camera over the rail today, after clearing it with Syracuse police and Air Traffic Control in Syracuse, a person who identified himself as part of the railroad security said the drone use was prohibited. A Syracuse police captain said he was deferring to railroad security.

Walsh today called on federal and NYS&W officials to release copies of annual bridge inspection reports. The reports -- kept by the railroad company -- are required under federal law.

He said that city officials had begun asking for records Thursday, and this afternoon the mayor sent official letters to the Federal Railroad Administration and the railroad seeking answers.

Walsh thanked FRA and NYS&W officials before asking for information.

"Fortunately, no injuries occurred as a result of the incident," Walsh wrote in letters, released to Syracuse.com. "Nonetheless, the collapse raises serious concerns for the city and the community regarding the elevated railroad through Syracuse."

Walsh asked for:

Most recent inspection reports on the elevated railroad in Syracuse

An immediate inspection of elevated railroad before resumption of train service

Provide information pertaining to the federal oversight in restoring service

Short- and long-term repair plans for the affected area, and the plan to restore service.

Walsh said that any inspections -- past or present -- were the purview of federal or rail company engineers.

There is no timetable for restoring service, Walsh said. He referred all other questions about what caused the collapse and the repairs to federal and railroad officials.

The FRA confirmed Thursday it was investigating the wall collapse in Syracuse. An FRA employee was at the scene today. The federal agency told a reporter to request inspection records under the Freedom of Information Act.

The railroad said this morning that it was building a temporary barrier along the collapsed wall. It was also adding temporary supports at three other locations on the 10-span bridge, based on a recommendation from its engineers.

Walsh said remaining areas of concern under the bridge have been blocked off and South Clinton would remain closed until further notice. An access road between Gifford and Dickerson streets, on the other side of the elevated tracks, was also closed pending repairs.

The mayor noted "significant progress" by the railroad in repairing the damaged structure. But the city incurred significant expenses in responding to the collapse. The mayor said he would demand full reimbursement from the railroad.