The Federal Bureau of Investigation is gathering information about the two men who opened fire outside an event last weekend in Garland, Texas. A security officer shot and killed the gunmen. The officer was wounded in the attack.
The shooting took place near a building where a private group was holding a contest. The group offered a $10,000 prize for the best depiction of Islam's Prophet Mohammad. For Muslims, any image or representation of the prophet is considered disrespectful.
The event was the idea of a group called the American Freedom Defense Initiative, also known as Stop the Islamization of America.
Police investigators searched the area where the shooting took place through the night and into the morning. Joe Harn is with the police department in Garland, Texas. He said police know what happened on Sunday.
"Two men exited the dark-colored sedan. Both of them had assault rifles, came around the back of the car and started shooting at the police car. The police officer in that car began returning fire and struck both men, taking them down."
Police used a robot to examine the suspects' car for explosives. They did not find any.
Later, investigators identified one of the dead men as 31-year-old Elton Simpson. He was born in the United States. As a young man, he accepted Islam. Police say he shared an apartment with Nadir Soofi, the other gunman, in Phoenix, Arizona.
Court documents say that Elton Simpson had been under investigation since 2006. They say he was tried and jailed in 2010 for lying to agents of the Federal Bureau of Investigation. He was suspected of wanting to join Islamic extremists in Somalia.
Federal agents and police searched the men's apartment home in Phoenix. Before carrying out the attack, Simpson is said to have provided details of his plans on the social media site Twitter.
The shooting has extended the debate about freedom of speech. Organizers of the contest described it as a free speech event.
Debate about freedom of speech
Pamela Geller was the lead organizer of the event in Garland. She compared the attack to the murder of 12 people earlier this year at Paris offices of the French weekly Charlie Hebdo.
Her group has created public debate over its opinions of Muslims in America. Her supporters say she speaks the truth about a topic people are too fearful to discuss. Her critics, however, call her a bigot. Oren Segal is with the Anti-Defamation League. The group describes itself on its website as dedicated to stopping the defamation of the Jewish people and to secure justice and fair treatment to all.
Mr. Segal said Ms. Geller "is one of the leading American anti-Muslim bigots, consistently vilifying Muslims and the Islamic faith under the guise of course of fighting radical Islamists." He said that she does not recognize a difference between Islamic extremists and all Muslims.
Ms. Geller answered criticism against her in an email to VOA.
She wrote that, "It is not bigotry to stand up for the freedom of speech and the freedom of expression against those who would violently suppress it," she wrote. "The ADL apparently prefers submission in the face of violent threats to standing up for the liberty and dignity of the individual."
The non-profit Southern Poverty Law Center has also condemned Ms. Geller's group.
In 2010, the American Freedom Defense Initiative campaigned against a proposed Islamic community center near the former World Trade Center towers in New York City. Terrorists with ties to al-Qaida destroyed the towers in 2001. The community center was never built.
On Tuesday, the Islamic State militant group claimed responsibility for the attack Sunday. There was no immediate comment from U.S. officials on the group's claim.
I'm Mario Ritter.