Water was still gushing down the street in Old City early Monday and a nearby hotel alarm was still sounding as city officials assessed the damage of Sunday morning's four-alarm blaze near Third and Chestnut Streets.

The fire ripped through two five-story apartment buildings and damaged several bars and restaurants, leaving 239 Chestnut St. beyond repair, city officials said Monday.

David Perri, commissioner of the Department of Licenses and Inspections, declared the building "imminently dangerous" and said it appeared to be a "total loss." The damage was so extensive that the owner was ordered to remove the fire escape to reduce the stress on the upper floors.

The building will have to be demolished, but officials are hoping to save the historic cast iron facade. Neighboring 237 Chestnut was also seriously damaged.

The Fire Marshal's Office is investigating the cause of the fire, which broke out around 3:15 a.m. Sunday and took firefighters more than nine hours to control. About 150 people were displaced. Neighbors reported hearing an explosion that shook the building.

The first floor of 239 Chestnut and of an adjacent apartment building had been occupied by the now-closed Revolution Diner. Property and court records list its owner as Imad Dawara, who previously operated a nightspot, Barra, and a hookah lounge, B Side, in the space.

On Monday, Dawara said he had closed the establishment due to medical problems that put him in and out of the hospital in the fall. He said he had intended to reopen the diner in the near future.

Dawara said that he was waiting to hear from officials on the cause of the fire and could not speculate as to how it started.

"I had my blood there," he said. "I'm so upset about what happened."

Sababa Vapes, an electronic cigarette shop next door at 237 Chestnut, was deemed "unsafe" due to fifth-floor structural damage, but L&I officials believe the building can be repaired.

Records show that 239 Chestnut has an open violation for failing to file a report on its fire escape inspection under a 2016 ordinance, but that  would not be connected to the cause or severity of the fire.

The owner of the building, Fresher Start Corp., could not be reached Monday.

Streets remained closed around Third and Chestnut on Monday and bus Routes 21, 42, and 57 were experiencing detours due to road closures in the area, a SEPTA spokesperson said.

L&I had begun to allow displaced guests from the Best Western Plus Independence Park Hotel back into the establishment to grab their belongings, Perri said.

City officials are asking displaced residents to call their building or property managers for updates from L&I — not to call 911.

"We all spent the night on the street watching our homes go up in flames," Al Gury, who lives in a studio apartment there, said. Gury said that he attempted to go back into his home to rescue his six cats and four parakeets.

A GoFundMe effort was set up in Gury's name, calling him "a caring part of the PAFA Community," referring to the Pennsylvania Academy of the Fine Arts. The page noted that Gury lost his "beloved cats" as well as his belongings. More than $39,500 had been raised by Monday evening.

The newly opened Museum of the American Revolution, across the street from the fire, was closed Sunday but reopened Monday.

A museum representative said more than 80 people were refunded for a breakfast event scheduled Sunday, while the institution took in 60 evacuees after it closed to the public.

Staff writers Jan Hefler and Mark Fazlollah contributed to this article.