KIEV, Dec. 26 - Yuriy Lutsenko, an opposition leader and an ally of former Prime Minister Yulia Tymoshenko, was arrested on Sunday, a move that sent shockwaves among Ukraine’s opposition groups.

The arrest of Lutsenko, a former interior minister, is the latest in a barrage of recent arrests and other forms of pressure against opposition figures that are affiliated with Tymoshenko.

Tymoshenko herself is under investigation and is charged with abusing power while in the government for allegedly diverting some of money from an environment account to social spending.

The Prosecutor General’s Office on Sunday declined to comment on Lutsenko’s arrest. He was last month investigated by prosecutors for allegedly misspending about $5,000 while in office.

“Lutsenko has been regularly appearing at the prosecutor’s office for questioning,” Yuriy Hrymchak, an opposition lawmaker and Lutsenko’s ally, said. “What has caused the arrest? This is the intimidation of Lutsenko and the entire opposition.”

The arrest sent shockwaves through opposition parties that fear the move has been politically motivated in order to intimidate the opposition.

“There are no doubts that the persecution of the former interior minister has been politically motivated,” Batkivshchyna, Tymoshenko’s party, said in a statement.