(CNN) -- East Timor's president Jose Ramos-Horta arrived in Australia on Monday on full life support after being shot twice in an assassination attempt in his country, a medical official said.
The Southeast Asian island nation's prime minister, Xanana Gusmao, was also attacked, but escaped unhurt, officials said. The coordinated assaults on their homes were blamed on rebel troops.
Ramos-Horta was shot twice in the back, and one of the bullets tore through his abdomen, Foreign Minister Zacarias da Costa said.
"We understand his condition is critical, but it has been stabilized with the emergency surgery in the military hospital, so that's good news," said Ian Badham a spokesman for Australia's CareFlight. The company dispatches medical teams via air ambulances.
Ramos-Horta arrived in Darwin, Australia, on Monday evening for the emergency medical treatment, a medical official said.
"He's in an induced coma. He's on a ventilator to control his breathing," said Badham.
"He certainly remains in a critical, but stabilized condition."
Ramos-Horta was taken to Royal Darwin hospital for additional emergency treatment. He underwent initial surgery at an Australian military hospital in East Timor before making the one-hour flight from the capital, Dili, to Darwin.
"It's possible he may have to undergo further surgery," Badham said. "Two bullet wounds can certainly cause a lot of medical damage." Watch as Badham describes Ramos-Horta's condition »
Gusmao was convening an emergency meeting of the island's government in Dili, Deputy Prime Minister Jose Luis Gutteres told CNN.
Australia, a close ally, said it would respond to Dili's request by sending several hundred troops and up to 70 police to help stabilize East Timor in the attacks' aftermath.
"I'm deeply shocked by developments this morning in East Timor," said Australian Prime Minister Kevin Rudd.
"What we had, apparently, are coordinated attacks aimed at assassinating the democratically elected leadership of East Timor, a close friend and partner of Australia."
Killed in the attack were a bodyguard for the president and two attackers, da Costa said.
One of them was rebel leader Maj. Alfredo Reinado, said Gutteres.
Reinado, the Australian-trained former head of East Timor's military police joined the revolt and became its leader. He was later captured but broke out of prison and returned to lead disaffected troops, said Damien Kingsbury, an analyst at Australia's Deakin University.
Two small parties in Gusmao's government had supported the rebels, and the government had been trying to coax Reinado to give up peacefully, Kingsbury said.
But a secondary plan had been developed to move against him by force if necessary, Kingsbury added, saying, "It's quite possible that he got wind of this plan and decided to act accordingly."
In a message to its citizens in the country, the U.S. State Department said the attack on the president occurred at 7:30 a.m. The State Department said there were "unconfirmed reports of unrest" in the Lahane zone of Dili and Taibesse but no other reports of unrest in Dili.
The U.S. State Department urged Americans "to use extreme caution and limit movements to the greatest extent possible."
Ramos-Horta shared the Nobel Peace Prize with Carlos Filipe Ximenes Belo in 1996 for their work toward a peaceful solution to the conflict in their country.
Under the rule of the late Suharto, Indonesia occupied East Timor for a quarter century, during which more than 100,000 people were killed, according to human rights groups.
East Timor gained independence in 2002.
In March 2006 a strike by about 600 East Timorese soldiers against alleged discrimination in the military led to their dismissal. The soldiers set up armed camps in the countryside, prompting the dispatch of additional peacekeepers from Australia, Malaysia, Portugal and New Zealand. E-mail to a friend