ANKARA (Reuters) - A Turkish court on Friday sentenced 25 people, including a former coastguard commander, to life in prison for trying to overthrow the government during a failed coup last year, state news agency Anadolu reported. Prosecutors had charged 28 people over incidents at a naval base in the northwestern province of Kocaeli on July 15, the night of the coup attempt. Three suspects were acquitted. The Ankara court named the coastguard commander as Hakan Ustem. The trial was one of the first in a series of cases against people accused of involvement in the failed putsch, in which more than 240 people were killed when rogue soldiers commandeered tanks, warplanes and helicopters and attacked state institutions including parliament. Earlier this month, a court found 42 former soldiers guilty of trying to kill President Tayyip Erdogan during the coup, handing most of them life sentences. The government blames the network of U.S.-based cleric Fethullah Gulen, a former ally of Erdogan, for orchestrating the failed coup.  Gulen, who has lived in self-imposed exile in Pennsylvania since 1999, has denied involvement and condemned the coup. 