"He believed in what he did and was always ready to help others," a friend described him.
The website of Italian newspaper Corriere Della Sera reported that Frammartino was working for the setting up of a children's supper camp for Palestinians in Jerusalem's Old City, and was supposed to return to Italy on Friday.
The youth was stabbed in the back while walking with four friends in the Sultan Suleiman street in the capital, near the Prahim Gate.
The attacker left the knife at the scene of the crime and fled. Police set up checkpoints in the area and arrested three suspects for suspected involvement.
It is believed that the attack was a nationalistically motivated terror attack, and not an attempted robbery.
Resuscitation attempts by Magen David Adom paramedics who arrived on the scene could not save him, and Frammartino was declared dead due to loss of blood.
Frammartino, a resident of Monta Rotondo, arrived in Israel at the start of the month with an Italian organization, ARCI, working to advance human rights in the world.
He planned for the experience for a year and was chosen with another youth from his city to take part in the project.
Frammartino was a law student. "He was very interested in politics and in the issues of society, like his father," said Monta Rotondo's Mayor, Anonino Lopi. "Something so beautiful ended in such a tragic way," he added.
The mayor expressed his condolescenes on behalf of the whole city.
'Not an extremist, just a pacifist'
In a letter sent a few months ago to a local newspaper, Angelo expressed his world view: "We must recognize that in a situation with no violence is a luxury in many parts of the world, but we are not seeking to prevent legitimate self defense operations. I never dreamt of condemning the resistance, the blood of the Vietnamese, the blood of nations under colonial occupation, or the blood of Palestinian youths from the first intifada," he said.
Angelo's neighbor said his parents were worried by their son's request to go on a 'different holiday,' but were proud of it and did not oppose. They set out on holiday, leaving their eldest daughter, Francesca, at home. She was alone when the news from Jerusalem came.
"My parents are on holiday. When they return, the house will never be the same as before," said a neighbor who burst out in tears. "He was a golden guy. He dealt with politics but he wasn't an extremist. He was just a pacifist, the poor guy."