Security officials said authorities have arrested a Lebanese army colonel on suspicion of spying for Israel, the second high-ranking military official detained in less than two weeks. The officials said the colonel was detained a few days ago as part of a stepped-up campaign against suspected Israeli spies that has produced about three dozen arrests. The first high-ranking military official arrested was also an army colonel who served as a commando officer. The officials did not provide details on the second colonel arrested. They spoke anonymously Monday because they were not authorized to release information. On Saturday, Lebanon charged four people with collaborating with Israel, raising to 23 the number of suspected spies who have been charged in the last few months, a court official said. Military prosecutor Saqr Saqr charged the four men with "collaborating with the Israeli enemy, aiding its forces and providing it with information about civilian and military positions and political and party figures," the official, speaking on condition of anonymity because he was not authorized to talk to the media. Since the recent crackdown began in April, Lebanon has arrested 35 people on suspicion of spying for Israel, the country's archenemy, Lebanese police commander Brig. Gen. Ashraf Rifi told The Associated Press. Lebanon considers itself at war with Israel and bans its citizens from having any contact with the Jewish state. Spying for or collaborating with Israel can be punishable by death.