Monday September 8, 2008  7:46 am

BEIJING (AP) - A Chinese woman detained for a month after protesting about being evicted from her home ahead of the Olympics has been freed, the woman and her son said Monday.

Zhang Wei said she was released on Saturday on condition that she keep her cell phone on at all times so police can contact her and order her back to jail if necessary.

``There was no reasonable explanation for why those conditions were attached to her release,'' Zhang's son, Mi Yu, said in a separate interview.

Mi said his mother had been told not to talk to reporters.

Telephones rang unanswered at the police station in the Chongwen district where Zhang was held.

Zhang has been vocal in the past two years about the pain caused by being forced out of her traditional family courtyard home in the Qianmen area near Tiananmen Square to make way for a commercial strip that opened a day before the Aug. 8 start of the Olympics.

She refused compensation for her home, and had gone every Monday to the district government's offices to plead her case.

During the games, an extremely sensitive period for China, authorities rounded up activists and others who applied to demonstrate in three areas that had been approved as official protest zones during the Olympics.

Zhang had sought permission to stage a protest at one of the zones in hopes of drawing attention to her plight after years of fruitless wrangling with local officials. Days later, she was taken from her home close to midnight. Police originally said she would be detained for three days, but later extended it to a month.

Mi said family members were unable to contact her while she was detained. Zhang said her husband tried calling the detention center many times but the phones were never answered.

The forced relocation of Beijing residents caught up in redevelopment projects is a hot-button issue for the government.

Just before the Olympics started, 20 people angry about their evictions from Qianmen demonstrated near Tiananmen Square. The protesters, who did not include Zhang, were dragged away by neighborhood officials as police watched.