(Reuters) - The release of police dispatch records offering new details from witnesses of the Orlando nightclub massacre provided fresh grist on Wednesday for the debate about whether law enforcement waited too long to take out the gunman.

Federal Bureau of Investigation (FBI) officials walk through the parking lot of the Pulse gay night club, the site of a mass shooting days earlier, in Orlando, Florida, U.S., June 15, 2016. REUTERS/Adrees Latif

About three hours passed on June 12 between the firing of the first shots and the killing of the hostage-taking shooter, prompting people to ask on social media and in emails to public officials whether quicker police action could have saved lives.

Orlando, Florida, authorities on Tuesday released new details including 911 operator notes and text and email messages received by the police chief whose officers fatally shot the gunman, Omar Mateen, after he killed 49 people and wounded 53 more.

The call log provides a minute-by-minute account as reported to emergency dispatchers, offering the most detailed timeline yet of the incident as it unfolded. The three-hour duration of the episode was already known.

Some critics said the transcripts showed police should have acted faster to remove the threat, but others argued they did the best they could in chaotic conditions.

Retired police sergeant Grant Whitus, who led the SWAT team during the Columbine High School shooting in Colorado in 1999, believes Florida officers should have pursued Mateen immediately inside the Pulse nightclub to “end it right there” before he could take hostages.

“How do you negotiate with a terrorist or mass murderer? You don’t,” Whitus said in a phone interview. “The more time you give him, the more people that are killed.”

That view was echoed by critics including Facebook user Chris Byrne, who said the delay amounted to gross misconduct. “Do I blame the responding officers? Absolutely not ... I blame their ‘leadership,’” Byrne wrote.

But several experts in tactical training and police performance cautioned against such judgments. They argued that, based on what is known so far, the deadliest mass shooting in modern U.S. history would have been even worse if not for the deliberate response by police.

“It’s always easy to second-guess and hindsight when you have time to sit and think about things. But when you consider how dynamic that situation was, their actions undoubtedly saved lives,” Thor Eells, board chairman for the National Tactical Officers Association, said in a phone interview.

Eells said he has trained SWAT members from the Orlando Police Department and other law enforcement agencies in Florida, and has been in contact with officers there since the shooting.

He and two other police veterans said the first officers at the scene responded appropriately by seeking out the source of the gunfire and trying to address the threat.

According to a timeline from the Federal Bureau of Investigation, officers from various law enforcement agencies entered the nightclub and exchanged gunfire with Mateen 6 minutes after the initial report at 2:02 a.m. of shots fired.

By 2:15 a.m., the police dispatch log said the shooter was trapped in a bathroom. Orlando Police Chief John Mina has argued that Mateen’s forced retreat allowed officers to rescue many people from elsewhere in the club.

However, other patrons who fled to the bathrooms as the gunfire erupted were now hostages. Someone in a bathroom whispered “please help” to a 911 operator and callers advised of victims losing blood, according to the police log.

The FBI said three crisis negotiation calls with Mateen, ranging from 3 to 16 minutes, occurred between 2:48 a.m. and 3:24 a.m.

“It’s very much a ‘damned if you do, damned if you don’t’ situation,” said Scott Reitz, a former SWAT operator and instructor for the Los Angeles Police Department. “So many things can go wrong.”

When police learned at 4:29 a.m. that Mateen was threatening to strap bomb vests onto hostages, they breached a wall of the club for what would be a final confrontation.

Jim Bueermann, president of the nonprofit Police Foundation, said an independent review of the incident should be conducted.

“At this point, criticism is unwarranted because we don’t have enough definitive information about what actually happened,” he added.