One of the three detained U.S. hikers left Iran on Tuesday evening after being released on bail of 500,000 U.S. dollars few hours earlier.

Sarah Shourd[Xinhua]

Xinhua reporter was told in Tehran's Mehrabad Airport that the female hiker Sarah Shourd left Iran for Oman on Tuesday evening.

"My client's mother has already travelled to Oman and now she is there," waiting for her daughter's arrival, said Masoud Shafiei, the Iranian lawyer of the three detained U. S. nationals.

The state-run IRNA news agency said that according to Tehran prosecutor's office, the release of the American female was made upon an order issued after the receipt of a bank guarantee on the sum of the bail.

But the tribunal has extended detention of the other two Americans, Josh Fattal and Shane Bauer, for another two months, Shafiei told the semi-official ISNA news agency.

Over the past weekend, Iran issued mixed messages over the release of Shourd.

Iran said Thursday that it would free U.S. female hiker on Saturday morning, but it abruptly halted her release, saying " judicial proceedings in the defendant's case have not been completed."

It, again, was followed by an announcement of the country's judiciary on Sunday that it was ready to release her on bail.

After her release from Iran's Evin jail at 4:40 p.m. local time (0110 GMT), Shourd joined the Swiss embassy officials in Tehran. Her psychological and physical state is good, ISNA said.

The embassy represents U.S. interests in Iran after the two countries broke direct diplomatic relations in 1980.

Tehran's prosecutor Abbas Jafari Dolatabadi said the release of the hiker has nothing to do with the case of Iranian scientist Shahram Amiri.

"We do not make any link between the two issues, Iranian judiciary fulfills its missions and only focuses on judicial issues," Dolatabadi was quoted by ISNA as saying.

In July, the 32-year-old Iranian scholar Shahram Amiri, who once worked at Iran's Malek Ashtar University and was missing on a pilgrimage in Saudi Arabia last year, arrived at Tehran's Imam Khomeini airport from the United States.

Media reports said that the scholar was released by the United States in exchange for the three American hikers who were arrested in Iran on July 31 last year for illegally entering the country from its western borders and were charged with espionage.

The U.S. government considered the charges totally unfounded and urged Iran to release all the three detained American hikers "on humanitarian grounds for many, many months."

"The hikers' release is long overdue," said Mark Toner, spokesman of the U.S. state department.

In May, mothers of the three Americans were allowed by the Iranian government to meet their children briefly in Tehran.