PARKLAND, Fla.: Students at a Florida high school where 17 of their classmates and staff members were killed returned Sunday to gather their belongings thrown down in panic during the school shooting nearly two weeks ago.

Thousands of students joined their parents in walking past the three-story building at Marjory Stoneman Douglas High School where the Feb. 14 massacre took place. It is now cordoned off by a chain-link fence that was covered with banners from other schools showing their support.

“Just seeing the building was scary,” freshman Francesca Lozano said as she exited the school with her mom. Still, she was happy to see her friends. “That made it a lot better.”

Seventeen people dressed in white costumes as angels stood by a makeshift memorial outside the school before moving near the entrance. Organizer Terry Decarlo said the costumes are sent to mass shootings and disasters so the survivors “know angels are looking over them and protecting them.” Many of Sunday’s angels were survivors of the 2016 Pulse nightclub shooting in Orlando where 49 people died, Decarlo said.

The school reopens Wednesday, and administrators said families would get phone calls about details later. Sunday was a day to ease into the return.

Earlier Sunday, Florida Gov. Rick Scott’s office said he had asked Florida Department of Law Enforcement Commissioner Rick Swearingen to investigate the law enforcement response to the shooting. The agency confirmed it would start the investigation immediately.

Broward County Sheriff Scott Israel has come under withering scrutiny after the revelation last week that Deputy Scot Peterson who was on the scene did not go in to confront the gunman during the attack. The department is also facing backlash for apparently mishandling some of the 18 tipster calls related to the suspected shooter Nikolas Cruz. The tips were among a series of what authorities now describe as the clearest missed warning signs that Cruz, who had a history of disturbing behavior, posed a serious threat.

Israel defended his leadership Sunday and said investigators were looking into claims that three other deputies were on the scene but failed to enter the school when the chance to save lives still existed. To date, the investigation has pointed to only one deputy being on campus while the killer was present, he told CNN.

Israel also labeled as “absolutely untrue” reports that the deputies waited outside even though children were inside the building needing urgent medical treatment.

Republican state Rep. Bill Hager of Boca Raton has urged Scott to remove Israel from office because of the missed red flags.

Israel vowed not to resign, saying Hager’s letter was “full of misinformation” and “shameful, politically motivated.”

House Speaker Richard Corcoran stepped up the pressure Sunday by signing a letter with more than 70 other lawmakers that calls on Scott to suspend the sheriff.

Israel insisted that lapses were being investigated. He told CNN that a deputy who responded to a Nov. 30 call referring to Cruz as a “school shooter in the making” was being investigated by internal affairs for not filing a report and had been placed on restrictive duty.

The FBI has acknowledged that it failed to investigate the tip about Cruz that the agency received on Jan. 5.

The Associated Press obtained a transcript of the more than 13-minute phone call. During the call, the woman described the 19-year-old Cruz as having the “mental capacity of a 12- to 14-year-old.” She pointed the FBI to several Instagram accounts where Cruz had posted photos of sliced-up animals and rifles and ammunition he apparently purchased with money from his mother’s life insurance policy.