A nurse has died after being burnt alive at a clinic in Israel by a man who was unhappy with the treatment she gave him, police say.
The suspect, a 78-year-old man, is reported to have had a flu vaccination about a week ago.
He had come back to the HMO clinic on Kaplan Street in Holon, south of Tel Aviv, daily since to complain about it and about the clinic's medical staff.
Police District Commander Sigal Bar-Tzvi said that the man was "apparently not satisfied (with his treatment) and while in an argument doused flammable material on the nurse that was treating him at the time."
Other reports suggest the suspect left the clinic before returning and setting a fire in the room where the nurse, 56-year-old Tova Kararo, was working.
An empty bottle and a lighter believed to have been used by the arsonist were found at the scene.
Bar-Tzvi called the incident "an extraordinary event and particularly shocking," and said the suspect fled by car but was later arrested by "large police forces."
A witness, Vladimir, said: "I was waiting in line when I heard screaming.
"When I approached, I saw the woman burning, surrounded by people trying to put the fire out. It was horrible."
A woman named Dorit, who was also inside the clinic, told a radio station: "The door to room six opened and suddenly I see a bottle on fire. A plastic fruit juice bottle that was thrown into the room.
"All of a sudden there was black smoke and boom boom like explosions," she added.
MDA medic Ofer Parentki told reporters: "When we arrived there was thick smoke at the scene after the fire was extinguished we located a woman without signs of life and determined her death at the scene."
Three other people were treated for smoke inhalation.
A police spokeswoman said the perpetrator was apparently "mentally unstable", while media reported he was a Holocaust survivor who thought the vaccination was an attempt to poison him.
One of Israel's labour unions announced a two-hour strike on Wednesday morning in tribute to Ms Kararo and in solidarity with health workers.