Des Moines, Iowa ? Four people were arrested during an anti-homosexual protest at a high school graduation where a gay student was given a scholarship.

They were accused of throwing cream pies Saturday at the followers of a Kansas-based anti-gay pastor.

The members of the Rev. Fred Phelps’ Westboro Baptist Church in Topeka, Kan., demonstrated at Des Moines Lincoln High School’s graduation at Veterans Memorial Auditorium.

The church members were protesting because senior class president Julius Carter was awarded a college scholarship in honor of Matthew Shepard, the gay Wyoming college student who was tortured and killed in 1998.

The First Friday Breakfast Club, an Iowa association of gay men, conducted a counterprotest.

Police Maj. Russell Underwood said officers were on hand for both groups’ safety.

“It’s a shame the pies had to be thrown,” Underwood said. “I thought we would get by with no arrests.

Barricades separated Phelps’ followers and the counter-protestors.

Shortly before the graduation began, four people dressed in black approached Phelps’ group and threw pies at them.

Police charged Timothy Bossenberg, 22, no address available, Sean Glynn, 20, of Des Moines, Kristen Chilcoat, 19, of Des Moines, and Lacey Hanson, 19, of Altoona, with disorderly conduct.

Lincoln High students helping with the commencement ceremony said the controversy about the senior class president has made the school stronger.

“I think it’s made more people have Lincoln pride, and it’s unified our school,” said Jessica Reese, a junior at Lincoln High.