A victim of an April 2015 attack on a Kenyan university at a hospital in Nairobi. Gunmen seized hostages in a pre-dawn attack. (SIMON MAINA/AFP/Getty Images)

Higher education communities worldwide have endured hundreds of attacks in the past four years, a barrage of persecution and violence that threatens academic freedom and scientific progress in Asia, Africa and elsewhere, according to a report released Tuesday.

The Scholars at Risk Network, based on the campus of New York University, said it documented 333 attacks on students, scholars, administrators and staff of colleges and universities in 65 countries from January 2011 through May 2015. The attacks included 111 incidents of killings, violence and disappearances; 67 of wrongful imprisonment; 47 of wrongful prosecutions; and dozens of other acts of intimidation against colleges and universities, such as travel restrictions or loss of academic posts.

“These attacks not only threaten the safety and well-being of scholars, students, administrators and staff,” Robert Quinn, the network’s executive director, said in a statement. “In conflict countries, like Syria and Iraq, failure to protect higher education will cripple any efforts to rebuild those societies when the fighting eventually stops, dragging everyone into a never-ending cycle of violence.”

Quinn said more protective measures also are needed “in fragile and volatile places like Pakistan, Thailand, Venezuela and Egypt … where universities, scholars and students are on the front lines in shaping the future of society.”

The 48-page report, believed to be one of the most extensive compendiums of its kind, was scheduled to be released at the United Nations Palace of Nations in Geneva. The network, founded in 2000, includes about 360 member institutions globally.

On April 2, Garissa University College in Kenya suffered one of the deadliest attacks of recent years. Gunmen affiliated with the al-Shabab militant group stormed the campus, killing students and taking hostages. At least 147 people died, and scores more were wounded.

[Al-Shabab attacks Kenyan university, killing at least 147]

In September 2014, the dean of Islamic studies at the University of Karachi was shot and killed by unidentified gunmen while en route to a reception to honor him. “Targeted killings include those aiming to silence particular individuals because of the content of their research, teaching, writing or public expression,” the report said.

Many of the attacks were not deadly, but they were nonetheless chilling.

The report cited the case of Azmi Sharom, a law lecturer at the University of Malaya, who in September 2014 was charged under Malaysia’s Sedition Act “for giving an interview to a newspaper in which he compared a current constitutional crisis with a similar crisis five years earlier.”

In August 2014, the report said, a student at Khon Kaen University in Thailand and an activist were arrested on charges of “insulting the crown,” for attempting to stage a satirical play called “The Wolf Bride.” They were each sentenced to two and a half years in prison.

“Overall incidents involving prosecutions and imprisonments threaten the heart of higher education by deploying coercive legal force to target academic speech, content and conduct,” the report said. It urged nations to repeal any laws wherever necessary “to ensure freedom to think.”