* Orthodox law supreme at Jerusalem's Western Wall
* Women activists hold monthly prayer sessions at site
JERUSALEM, Feb 11 (Reuters) - Israeli police detained 10 women at one of Judaism's most sacred sites on Monday for wearing prayer shawls, which Orthodox tradition sees as solely for men, a spokesman said.
The incident at the Western Wall in Jerusalem's Old City highlighted the divisions between the more liberal streams of Judaism and politically powerful Orthodox groups that traditionally limit the role of women in prayer.
The Western Wall is administered under strict Orthodox ritual law, which bars women from wearing prayer shawls or publicly reading from the holy scriptures.
Among those held was Susan Silverman, a reform rabbi who is a sister of U.S. comedian Sarah Silverman. Two other American citizens and Israeli members of "Women of the Wall", a group that campaigns for gender equality in religious practice, were also detained.
The group routinely convenes for monthly prayer sessions at the Western Wall, revered by Jews as a perimeter wall of the Biblical Temple in Jerusalem. Some of its members have been detained by police in the past for wearing prayer shawls at the site and released without charge.
Susan Silverman, who immigrated to Israel from Boston, said police escorted the group, including her 17-year-old daughter, to a station after they refused to remove prayer shawls.
The rabbi said in a telephone interview from the police station where the group was held that they had been among more than 100 women attending the hour-long prayer session.
"They (police) said 'take off your prayer shawls', and we said 'no'," Silverman said. Once the prayers were over they were escorted away, she said.
Micky Rosenfeld, a spokesman for national police, said the women had acted "against regulations set by the High Court", citing a decision of a decade ago upholding Orthodox rules at the site to avoid friction between worshippers.
Silverman said the Orthodox tradition barring women from wearing prayer shawls amounted to "spitting on Sinai", naming the site where the Bible says God handed the ancient Israelite leader Moses the 10 Commandments.
"All Jews are in a covenant with God," regardless of their gender, she said. (Writing by Allyn Fisher-Ilan; Editing by Alison Williams)