Hate crimes in 2015 were more than 6 percent more frequent than they were in 2014, with a two-thirds increase in religiously motivated attacks against Muslims.

The FBI's Hate Crimes Statistics, 2015 report tallied more than 5,850 hate crime incidents in 2015.

Most of the crimes were intimidation, vandalism or assault.

Most of those — 56.9 percent — were racially motivated, with more than half of race-based attacks targeting African-Americans.

But religiously motivated attacks were a growing share of the tally. Incidents of religious hate crimes rose by nearly 23 percent compared to 2014.

Most hate crimes based on religion targeted Jewish people; anti-Semitic attacks were up more than 9 percent compared to 2014.

Attacks on Muslim-Americans, meanwhile, rose an eye-popping 67 percent.

That puts attacks against Muslims at their highest levels in a decade and a half, The Associated Press reports:

"In 2015, there were 257 incidents of anti-Muslim bias compared to 184 incidents the prior year. The total is second only to the surge in hate crimes following the 9/11 terror attacks in 2001."The increase could be due, in part, to increased reporting by victims as well as better reporting and tracking by law enforcement agencies, although the number of all law enforcement agencies sending their data to the FBI decreased about 3 percent between 2014 and 2015."

Attacks based on sexuality and gender identity were up by 4.6 percent, while attacks based on gender or disability decreased slightly, according to the FBI report.

The FBI report is based on local law enforcement data. It almost certainly understates the scale of the problem: In 2014, the Bureau of Justice Statistics estimated, based on victim surveys, that 60 percent of hate crimes are never reported to police.

The annual hate crimes report always comes out toward the end of the year. This year, it happened to be released as the country was already discussing the frequency of hate crimes — based on alleged acts of violence and intimidation in the wake of the presidential election.

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