MOSCOW, February 12. /TASS/. Lawyers of Paul Whelan, a US citizen accused of spying in Russia, have filed an appeal against his custody with the Moscow City Court’s cassation instance, his lawyer Vladimir Zherebenkov told TASS on Tuesday.

"In our appeal we ask to cancel the decision by the Lefortovsky court on arresting Whelan and also to reverse the ruling of the Moscow City Court, which upheld his arrest," the lawyer said.

He asked to release his client on a 5 mln ruble ($76,200) bail or place him under house arrest either in a rented apartment or in a hotel.

Russia’s Federal Security Service (FSB) said Paul Whelan was detained in Moscow "while he was on a spy mission." The FSB Investigative Department opened a criminal case under Article 276 of the Russian Criminal Code (espionage), which carries a punishment of 10 to 20 years in prison. Whelan holds citizenship of the US, UK, Ireland and Canada. In early January, US Ambassador to Russia Jon Huntsman visited Whelan at the Lefortovo pre-trial detention center.

Whelan, 48, is corporate security director for US automotive parts supplier BorgWarner. According to the Washington Post, he enlisted in the US Marines in 1994 and "rose through the ranks to become a staff sergeant, serving two tours in Iraq, in 2004 and 2006." However, Whelan "was discharged for bad conduct in 2008 after being convicted of several charges related to larceny.".