Former Philippines president Gloria Macapagal Arroyo, who is facing a corruption investigation, has been prevented from flying to Singapore for medical treatment by immigration officials.
The order to block Arroyo's trip on Tuesday followed a supreme court ruling that gave her - along with her husband - permission to travel abroad for medical treatment.
The court overruled Benigno Aquino, the current president, who argued that the Arroyos would not return because they are being investigated over allegations of corruption and electoral cheating.
"They weren't able to board the airplane," said Arroyo's lawyer Raul Lambino, accusing the government of inflicting "inhumane, cruel punishment" on his client.
Arroyo and her husband later left the airport in the ambulance and headed to a hospital where she was to be checked for stress, said an ally, Rep Edcel Lagman.
"They are very mean. They are very cruel," husband Jose Miguel Arroyo said of the government. "I feel sad. I feel mad. How can they refuse to follow the supreme court order? That is tyranny."
Al Jazeera's Marga Ortigas, reporting from the capital Manila, said Arroyo had been wheeled into the airport terminal and was in the company of her husband and her eldest son - ready for the flight.
She said the supreme court was contesting the decision of immigration officials and the justice department to block Arroyo's trip, saying its orders were above those of other judicial bodies.
"The justice secretary has accused the supreme court judges of having been bought since the judges who ruled in Arroyo's favour were actually technically all voted into their positions by her when she was president," said our correspondent.
"There's a lot of legal wrangling ... Already Arroyo's lawyers have said that though she has gone back to the hospital, which has been her home for the past few weeks, this doesn't mean she is defeated."
No formal charges
The health secretary met Arroyo and her doctors last week and said her situation was improving and was not life-threatening, said Ortigas.
Aquino offered to fly in foreign doctors to provide medical treatment for Arroyo, who has not been formally charged since she left office.
Our correspondent quoted Leila de Lima, the justice secretary, as saying the government did not want to rush the case and would ensure that Arroyo and her family do not escape justice.
Arroyo, currently a member of congress, is under investigation over several allegations of corruption and electoral fraud during her 2001-2010 presidency. She has denied any wrongdoing.
The supreme court set several conditions for her departure, requiring the Arroyos to post a roughly $40,000 bond and designate a legal representative to act on their behalf. The couple is also required to present themselves to the Philippine embassy at their destination.
Arroyo has already undergone three spinal surgeries in Manila, and was shown in photographs distributed by her lawyer wearing an elaborate neck brace. She is also suffering from a parathyroid ailment, her doctors say.