Japanese police said Friday that they are keeping an American man in custody for 10 more days before authorities decide whether to press charges against him for snatching his children from his ex-wife.

Christopher Savoie, of Franklin, Tennessee, was arrested Sept. 28 after allegedly grabbing his two children, ages 8 and 6, from his Japanese ex-wife as they walked to school. He will remain held in city of Yanagawa where he was arrested, on the southern island of Kyushu, police official Kiyonori Tanaka said.

Savoie's Japanese lawyer, Tadashi Yoshino, was not immediately available for comment.

The case is among a growing number of international custody disputes in Japan, which allows only one parent to be a custodian — almost always the mother. That leaves many divorced fathers without access to their children until they are grown up.

That stance has begun to raise concern abroad, following a recent spate of incidents involving Japanese mothers bringing their children back to their native land, and refusing to let their foreign ex-husbands visit them.

The United States, Canada, Britain and France have urged Japan to sign the 1980 Hague Convention on International Child Abduction. The convention, signed by 80 countries, seeks to ensure that custody decisions are made by the appropriate courts and that the rights of access of both parents are protected.

Tokyo has argued that signing the convention may not protect Japanese women and their children from abusive foreign husbands, but this week Foreign Minister Katsuya Okada said officials were reviewing the matter.

Tanaka said that Savoie's Japanese ex-wife, Noriko Savoie, is staying with her Japanese parents in Yanagawa with the children, but they have refused to talk to the media.

The family lived in Japan from 2001 and early 2008. They moved to the U.S. in January 2008, immediately after which Christopher filed for divorce. In August, Noriko secretly brought the children to Japan.

Savoie could face up to five years in prison if convicted of the crime of kidnapping minors. Tanaka said Savoie has told investigators that he was aware what he did was in violation to Japanese law.

U.S. Consulate spokeswoman Tracy Taylor said Thursday that American officials have visited Savoie regularly since his arrest, and that he appeared "okay physically."