An appeals court in Qatar has cleared a US couple sentenced to three years for the neglect of their adopted daughter, in a case that was closely watched.
The court ruled Matthew and Grace Huang not guilty of starving to death their daughter Gloria, originally from Ghana.
Mr and Mrs Huang were sentenced in March but were allowed to remain free in Qatar pending their appeal.
They went to the airport after the decision but say they were barred from leaving and their passports were taken.
A post on the Facebook page for the campaign to get them released said that a travel ban remained, and that the Qatari authorities had issued a warrant for their arrest earlier on Sunday.
Family representative Eric Volz told the Associated Press news agency officials had informed the couple that a new appeal had been filed in their case.
He added that the US ambassador - who went to meet them at the airport - was trying to intervene.
The Los Angeles couple were convicted of child endangerment over the death of Gloria, eight, in January 2013.
They say the little girl died of medical problems complicated by unusual eating habits that included periods of binging and self-starvation.
Prosecutors alleged she had died after being denied food and being locked in her room.
According to a website campaigning for the couple's liberation, Qatari police had accused them at one stage of starving Gloria to death in order to harvest her organs or to perform medical experiments on her body.
Such suggestions were "ridiculous", the couple said.
The couple's other two children, also adopted and of African origin, were placed in government custody but eventually permitted to return to the US with Mrs Huang's mother.
"Grace and I want to go home and be reunited with our sons," said Matthew Huang after Sunday's ruling.
"We have been unable to grieve our daughter's death but we want to thank the judge for today's decision. We're looking forward to returning to the US."
The American couple and their children moved to Qatar in 2012 when Mr Huang, an engineer, got a job working on a construction project for the 2022 Fifa World Cup.
Western-style adoptions and cross-cultural families are relatively uncommon in the Gulf state, correspondents say.
US officials intervened on the couple's behalf, with state department spokeswoman Jen Psaki last month urging Qatar to lift the travel ban immediately and bring the case to an "expeditious and just conclusion".