PHILADELPHIA — The Drexel University student who was arrested along with two other Americans by Egyptian police after allegedly throwing Molotov cocktails during a pro-democracy protest has been released from the police station where he had been in custody, his attorney said Friday.

Theodore Simon, a Philadelphia lawyer representing the family of Gregory Porter, said that “certain necessary administrative steps” that precluded the student’s release from police custody had been resolved and that he expected his client to be on his way home “very soon.”

“He was permitted to leave,” said Simon.

Porter, 19, and two other students, Luke Gates, 21, of University of Indiana, and Derrik Sweeney, 19, of Georgetown University, have been detained since Monday when they were arrested for allegedly throwing firebombs at police from a rooftop in the American University compound during protests. The campus is near Tahrir Square, the heart of the protests. Sweeney and Gates apparently have also been released.

On Tuesday, the U.S. Embassy in Cairo issued an emergency message for all U.S. citizens cautioning them to avoid Tahrir Square and to abide by all local laws.

Lori Doyle, spokeswoman for Drexel University, said three other students from the school are attending the American University in Cairo.

“We have talked to them and their families and they have all agreed they would like to stay there,” she said. Those students are on the main campus, about an hour away from Tahrir Square, she said. They have been cautioned to stay on campus and away from protests, she said.

Simon said he is working with co-counsel in Egypt. A release order was entered and prosecutors agreed not to appeal, he said.

Porter, of Glenside, Pa., and a graduate of La Salle College High School, has been studying at the American University. His mother, Nancy Hansen, lives in Glenside.

Simon, who recently represented Amanda Knox, the American exchange student whose murder conviction in the death of her roommate in Italy was recently overturned, said he was able to talk with Porter while he was detained. The student said he was treated OK.

“He presented himself as someone much more mature than his 19 years, given the extraordinary difficulties he was facing,” said Simon. While a lot has happened in a short time, Simon said, Porter’s family was still waiting with some concern.

“Until they give him a warm hug, it won’t be over,” Simon said.

On Friday, a statement on the American University’s website said “ … staff members from the International Student Affairs office and the International Peer Leaders visited with the students and found them well. They will continue to visit the three students until their release and departure.”