CLEVELAND, Ohio -- Serial vandalism at an abortion clinic in Cleveland last summer is one of several instances referenced in a national abortion rights group's report regarding a nationwide spike in trespassing, obstruction and threats at abortion clinics.

The National Abortion Federation, which tracks violence at abortion clinics, reported that incidents of trespassing doubled and threats against workers or patients at the clinics tripled from 2016 to 2017. The organization blamed the national political climate for the upsurge in activity.

The report said instances of vandalism have decreased, but damages in individual instances have increased, including the $32,000 worth of damage caused by a serial vandal at Preterm in the 12000 block of Shaker Square in Cleveland, Ohio's largest abortion clinic.

Someone threw a brick through a window of the building on June 1, June 12 and June 19.

No arrests have been made, and investigators have not been able to identify the vandals, one of which was captured by surveillance cameras in the June 12 incident.

Cleveland police released surveillance footage in the hopes that the public would provide tips on the identity of the vandal, but no arrests have been made.

Vicki Saporta, the president and CEO of the National Abortion Federation, said she worked with Preterm in helping set them up with the FBI, which she said is investigating the case. FBI spokeswoman Vicki Anderson declined to confirm if the FBI was investigating the case.

Saporta said her group, Preterm, the FBI and Cleveland police have a good working relationship.

"The FBI has been very responsive in Cleveland in terms of their investigation," Saporta said. "We certainly hope they can identify perpetrator and bring them to justice. Law enforcement is the key across the country for responding to and deescalating violence."

Messages left at Preterm were not returned.

The National Abortion Federation compiled the numbers based on monthly reports from abortion providers.

The found a significant increase in activity aimed at intimidating patients and providers, citing 1,704 cases in 2017, up from 580 in 2016. Death threats also rose to 62 from 33, the survey said.

NARAL Pro-Choice Ohio spokesman Gabriel Mann said abortion providers across the state have to deal with protesters daily. The national survey said 78,114 protests were reported in 2017.

"It's a daily issue here for all our providers," Mann said. "When someone's heading to the doctor, the last thing they want is to be harassed by someone. We've been working with local officials and police to combat this problem."

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