The New York City Police Department is again being accused of anti-LGBT harassment, as a new study indicates that homeless LGBT youth are are being repeatedly harmed by NYPD officers.

The Urban Institute surveyed 283 homeless LGBT youth in New York City who currently engage in survival sex -- sex in exchange for shelter and food -- and found that 71 percent have had interactions with the NYPD, most of them negative and often turning physical.

Seventy percent of the youth said they had been arrested at least once, usually for crimes like fare evasion. Of those arrested, 49 percent said they felt "unsafe" in the patrol car after the arrest, and had experienced violence at the hands of officers.

"This abuse consisted of verbal harassment, physical assault such as beating and choking, sexual assault including being propositioned for sex in exchange for release from custody and rape, denial of help when reporting a crime against police, and destruction or theft of personal property," the report says. "In addition to physical injury, youth identified police violence as leading to psychological injury, including post traumatic stress disorder."

Meredith Dank, senior research associate at the institute, says that although this sample was specific to homeless LGBT youth in New York City, such experiences are not unique to them. "This is happening on a national level," she told Newsweek. "LGBTQ youth are experiencing police discrimination and abuse, especially those who are engaging n survival sex to have their basic needs met."

Homeless LGBT youth are seven more times likely to trade sex than heterosexual youth, according to an earlier study conducted by the Urban Institute titled "Surviving the Streets of New York."

The True Colors Fund, an organization that supports homeless LGBT youth cofounded by singer and activist Cindy Lauper, cites "family conflict" as the most common cause of LGBT youth homelessness. "For LGBT youth in particular, the conflict tends to be over their sexual orientation or gender identity," the organization's website notes. "Half of all teens get a negative reaction from their parents when they come out to them. More than one in four are thrown out of their homes."

LGBT youth are disproportionate represented among homeless youth in the United States. According to the study, LGBT youth make up five to seven percent of the overall youth population but 20 to 40 percent of the homeless youth population.

The study is the latest example of accusations that the New York police mistreat LGBT people. In August, Jacob Alejandro filed a federal lawsuit against the NYPD alleging that officers held him down, broke his ribs, and used antigay slurs against him as he tried to leave the city's Pride celebration in 2014. In July, Louis Falcone, a gay black man, reported being beaten by police outside his Staten Island home the previous month. The department has also often been criticized for transphobia.