TAMPA, Florida (REUTERS) - The gunman who killed 49 people at a gay nightclub in Orlando in the worst mass shooting in modern US history has been buried at a Muslim cemetery in southern Florida, media reported on Thursday (June 23).

A state death certificate lists Omar Mateen's burial site as the Muslim Cemetery of South Florida in Hialeah Gardens, a city in Miami-Dade County, according to the Orlando Sentinel newspaper.

Mateen, 29, was killed after taking hostages during a three-hour standoff inside the Pulse nightclub by police who ended his June 12 attack, which also wounded 53 people.

A funeral home located at the same address as the cemetery carried out the arrangements, the state document showed. It did not give Mateen's cause of death, the Sentinel reported.

The cemetery could not immediately be reached for comment.

Mateen, a US citizen born in New York to Afghan immigrant parents, claimed allegiance to the leader of the Islamic State militant group during a phone call with authorities during his rampage.

US authorities have said the attack was both terrorism and a hate crime. They do not believe that Mateen, who lived in Fort Pierce, Florida, with his wife and young child, had received assistance or orders from abroad.

The massacre took place during a Latin night celebration at Pulse, which on Thursday was planning a Latin night street party to benefit employees of the club. Pulse has been closed since the shooting.