Jessica Durando

USA TODAY

Muslims across America showed an outpouring of support for victims after the deadliest shooting spree in U.S. history left 49 people dead in an Orlando, Fla., nightclub.

The lone shooter, killed by police, has been identified as a Muslim.

A federal law enforcement official told USA TODAY the suspect has been identified as Omar Seddique Mateen of Fort Pierce, Fla. The official, who did not want to be named because of the sensitivity of the investigation, said authorities are trying to determine if the shooting was connected to radical Islamist groups such as the Islamic State.

Rep. Adam Schiff, D-Calif., a member of the House Intelligence Committee, said earlier Sunday that he was informed that Mateen had declared allegiance to the Islamic State during a communication with law enforcement at some point before he died.

The suspect's father, Mir Seddique, told NBC News on Sunday that his son had recently expressed anti-gay sentiments. He said the attack "had nothing to do with religion."

Orlando nightclub shooting: What we know

The Florida chapter of the Council on American-Islamic Relations issued a statement that said, "We condemn this monstrous attack and offer our heartfelt condolences to the families and loved ones of all those killed or injured. The Muslim community joins our fellow Americans in repudiating anyone or any group that would claim to justify or excuse such an appalling act of violence."

The Muslim civil liberties organization is asking for blood donations to help those injured in the attack.

The American Muslim Community Centers, a mosque in Longwood, Fla., said the mosque stands with Americans and "senseless violence has no place in our religion or in our society."

''The American Muslim Community Centers is saddened and shocked by the senseless killings in downtown Orlando, and we pray for the victims and their family members," said Chairman Atif Fareed.

People were quick to turn to Twitter to express disapproval of the attack and explain that it does not reflect the values of the U.S. Muslim community:

Rafat Ali tweeted, "As an American Muslim in month of Ramadan, hard to comprehend except to say LGBT community has stood for us, our time to do same."

Imam Tariq Rasheed of the Islamic Center of Orlando echoed those sentiments. "No religious tradition can ever justify nor condone such ruthless and senseless acts of violence. Our prayers and condolences go out to the family and loved ones of the victims." Rasheed said.

“We are very saddened,” said Imam Muhammad Musri, president of the Islamic Society of Central Florida. “We condemn the person who did this, whatever ideology he had. No lives should be lost because of anger and hate.”

Officials: Orlando suspect a U.S. citizen; probe underway for terror ties

Musri, who is also president of American Islam, said he does no know what could be done for what seems like one mass shooting after another.

“I condemn all acts of terrorism, especially those done in the name of my faith,” he said. “It’s heartbreaking to see this in my beloved city of Orlando. We’re in mourning.”

Concerns grew of a backlash against Muslim Americans following the shooting.

President Bilal Rana of the Ahmadiyya Muslim Youth Association said in a statement, "We urge all Americans to hold fast together against such violence and hate that seeks to divide and antagonize all of us.”



In the wake of the Paris and San Bernardino, Calif., terror attacks last year, the Center for the Study of Hate and Extremism at California State University released a study in December 2015 indicating that hate crimes against Muslims had tripled since the two attacks, reaching levels not seen since the immediate aftermath of Sept. 11, 2001, according to the International Business Times.

Contributing: Chris Bonanno

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