JERUSALEM (AP) — An American educator and peace activist who worked for coexistence and who died this week from wounds sustained in a Palestinian attack is the lead plaintiff in a lawsuit against Facebook for allowing gruesome Palestinian pages that incite violence, his son said Thursday.

The lawsuit was filed in the United States by Israel-based rights group Shurat Hadin, days before 76-year-old father Richard Lakin died.

Lakin, an elementary school principal and a 1960's civil rights activist in the U.S., worked for peace and coexistence in Israel until he was critically wounded on Oct. 13, when two Palestinian men boarded a bus in Jerusalem and began shooting and stabbing passengers.

It was one of the bloodiest attacks in a month of violence that has seen almost daily assaults by Palestinians, mostly with knives, against Israeli civilians and soldiers. Eleven Israelis have been killed in Palestinian attacks. In that time, 58 Palestinians have been killed, 38 said by Israel to be attackers, and the remainder killed in clashes with Israeli security forces.

Israel says the outburst of violence is the result of Palestinian incitement. Palestinians say the violence is due to a lack of hope for gaining independence after years of failed peace efforts.

These Palestinian postings include caricatures and video reenactments demonizing Israelis, graphics with instructions on "how to stab a Jew," and calls for attacks on Facebook before carrying out stabbings. Other posts glorify the gruesome Palestinian attacks and hail the murderers as heroes.

Lakin was originally from Newton, Massachusetts, and a longtime principal in Glastonbury, Connecticut. In the 1960s, he marched with Martin Luther King and was a Freedom Rider, working to desegregate the South.

His Facebook page displayed an image of Israeli and Arab kids hugging under the word "coexist."

Lakin's son Micah Avni said his father was shot in the head and then stabbed multiple times — in much the same way as described in some of the videos posted online.

One of the Palestinians who killed his father had previously made his intentions clear on Facebook and his posts were widely reposted on social media afterward, Avni said.

Avni said the day after the attack, a video reenactment of the assault on the bus was posted, "showing how to butcher people and encouraging others to do so." He said the video is still on YouTube, two weeks later.

He added that social media companies "must recognize their social and ethical responsibility" to ban posts that encourage murder and detail how to commit it.

Shurat Hadin said 20,000 Israelis are suing Facebook over the Palestinian incitement.