A 15-year-old boy was killed and 14 others wounded in two suspected bomb attacks at bus stops in Jerusalem, Israeli police say.
The explosions occurred in two crowded city outskirts areas as people headed to work.
The teenager who died was a Canadian-Israeli Jewish seminary student named Aryeh Schupak.
Israel’s prime minister said it was an attack “unlike what we have seen in recent years.”
The atmosphere feels volatile in a year of escalating violence. Palestinian gun and knife attacks have targeted Israelis, and Israeli military incursions have killed Palestinian gunmen and civilians in the occupied West Bank.
No group has so far said it was behind the explosions. However, the Palestinian militant groups Hamas and Islamic Jihad praised the perpetrators of what they called the “operation”.
The first explosion occurred in Givat Shaul, near the main entrance to Jerusalem, shortly after 07:00 (05:00 GMT) on Wednesday.
Israeli medics said the blast injured 12 people, including the teenager who died at the Shaare Zedek Medical Center.
About 30 minutes later, there was a second explosion at Ramot Junction, another entrance to the city. It left three people with minor injuries.
At the site of the first explosion, the pavement was covered in rubble. Masked Israeli security forces sealed off the site while parts of a badly damaged bicycle were placed in forensic bags.
A man from an ultra-Orthodox Jewish neighbourhood across the street told the BBC he was woken up when his building shook. Many of those waiting for the buses were from the community.
A small protest was also taking place with a banner held by young Israelis calling for “revenge”.
The head of the Israeli police’s operations division, Deputy Commissioner Sigal Bar Zvi, said the bombs were made with “high quality” explosives and placed in a bush and behind a wall at the bus stops.
Given the nature of the attacks, she added, investigators suspect they were masterminded by an organised cell.
Israeli media cited security sources as saying both devices contained nails and were likely to have been detonated remotely.
Following a meeting with Israel’s security chiefs, outgoing Prime Minister Yair Lapid said Aryeh Schupak “was a boy who never wronged anyone in the world, and he was murdered simply because he was Jewish”.
He also pledged that security forces would “find these heinous terrorists, those behind them and those who provided them with weapons”.
“I want to say to the citizens of Israel: We will find them. They can run and hide – it won’t help them; the security forces will reach them. If they resist, they will be eliminated.”
On Tuesday night, Palestinian health officials said that a 16-year-old Palestinian boy named Ahmad Amjad Shehada was shot dead during clashes with Israeli forces in the northern West Bank city of Nablus.
The Israeli army said its troops fired on “armed suspects” during an operation “to secure the entry of Israeli civilians into Joseph’s Tomb.” The tomb is revered by Jews, who believe that the biblical figure of Joseph is buried there.
In a separate incident Tuesday in the nearby city of Jenin, Palestinian gunmen seized the body of a 17-year-old Israeli Druze boy who was fatally injured in a traffic accident near Jenin, his family said.
Tiran Fero’s uncle told the Haaretz newspaper that he was in Jenin’s Ibn Sina hospital with his nephew when a group of men “fired their weapons into the air and yelled in Arabic,” then “disconnected him from the life support machines and dumped in a vehicle.”
“If Tiran’s body is not returned, the kidnappers will pay a heavy price,” Lapid warned Wednesday.