U.S. Sens. Bob Corker, R-Tenn., ranking member of the House Foreign Relations Committee, Lamar Alexander, R-Tenn., and Roy Blunt, R-Mo., sent a letter Tuesday to Kerry warning of the dangers to Christians in Egypt.
"Egypt's Christian minority and their ability to worship are in danger," the letter read. "The situation warrants a clear U.S. response."
Ahram Online reported four people were killed last weekend and 18 others were injured when gunmen fired on a wedding at a Christian church in Cairo. The Egyptian government described the attack as "cowardly."
Violence against Christians is not new. Nearly two dozen members of the Coptic community were killed in an attack on a church in Alexandria in January 2011.
"The U.S. must respond to this challenge and continue to be a forceful defender of religious freedom throughout the world," the senators said.
The U.S. government this month announced it was suspending some military assistance to Egypt in response to violence that erupted in the wake of the July ouster of President Mohamed Morsi.