|Al-Hosni appeared on Syrian state television on Tuesday, saying she had ran away from her family
Rights groups have said they "regret any inaccuracy in the misidentification" of the body of a girl that became an icon in the Syrian uprising.
Opposition activists and rights groups had reported that Zaynab al-Hosni, 18, was found in a morgue with her head and extremities cut off after vanishing from her home in the city of Homs in July.
But Syrian state television aired an interview with al-Hosni on Tuesday, saying she left her family’s house to escape ill-treatment by her brothers.
Human Rights Watch and Amnesty International, the international human-rights monitors, said in a joint statement on Wednesday that her family had confirmed that the woman interviewed was indeed al-Hosni.
Graphic video footage of the mutilated body activists said was the remains of al-Hosni was posted online and triggered outrage among the opposition. Protesters carried the picture of the woman dubbed the "flower of Syria".
The rights groups said they regularly verify their information with multiple and independent sources, and that Amnesty International had spoken directly to one of al-Hosni's brothers before reporting the case.
"Human Rights Watch later interviewed in person al-Hosni’s mother, as well as a brother who washed the corpse prior to burial, after they had escaped Syria to a neighbouring country," the statement said.
"It now appears that Zaynab’s family misidentified the body that was presented to them due to the extensive damage to the body."
Call for investigation
The identity of the female appearing in the video purporting to show al-Hosni remains unknown, and Amnesty International and Human Rights Watch have called for an independent investigation to reveal her identity.
Al-Hosni's family said they had received a phone call saying she was in custody.
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The mother later came across the body while looking for her son Mohammed, who had been active in anti-government protests. Human Rights Watch said his body had multiple bullet wounds when his mother claimed it.
Homs has witnessed some of the largest rallies since anti-government protests began in March.
Security forces have responded with a bloody crackdown on dissent, and activists say thousands of peaceful protesters have been killed.
Meanwhile, there has been an increase in reports of attacks on security forces by armed opposition elements.
And in Homs, several intellectuals have been killed in recent weeks, with suspected sectarian motives.
It remains unclear who was responsible for the death of Saria Hassoun, the son of Syria's grand mufti, a religious leader who supports the leadership of President Bashar al-Assad.
In the latest reports of bloodshed, activists said four soldiers were killed and several civilians injured on Thursday in clashes between troops and deserters in Jabel al-Zawiyah in the northern Idlib province.
The UK-based Syrian Observatory for Human Rights said troops and security forces had attacked villages in the region.
The Local Co-ordination Committee said two people were killed after the army stormed the village of Lej.
Source: Al Jazeera