A man who fatally stabbed his mother-in-law, then told police they were attacked by intruders, was sentenced to 30 years in prison Wednesday by a Prince George’s County Circuit Court judge, State’s Attorney Angela D. Alsobrooks said.

Ranulfo Alejandro Vargas, 25, was sentenced for the murder of Cristela Bermudez Leon, who was 39 when she was killed on April 12, 2010.

On March 25, a Circuit Court jury convicted Vargas of second-degree murder. The sentence was set by Circuit Court Judge Michael Whalen.

Bermudez Leon was killed inside her Riverdale home in the 6600 block of 60th Avenue. Police found her body inside a bedroom on the ground floor of the two-level home. She had been stabbed about 40 times, and she had a broken nose that was bleeding heavily.

Vargas told investigators that three black men had broken into the house, demanded money, and attacked Bermudez Leon and him. Two of the men, both armed with a knife, took Bermudez Leon into the ground-floor bedroom and stabbed her, Vargas said.

Vargas said he broke free from the third attacker, who was holding him at bay with a gun, and tried to save his mother-in-law, but slipped in a pool of blood.

County police were immediately suspicious of Vargas’s account, and interrogated him at length. More than an hour of the videotaped interrogation was played for the jury at Vargas’s trial.

At his trial, Vargas took the witness stand and testified that he made up the story about the intruders because he was scared and confused. He testified that h is mother-in-law was scolding him for not paying rent, then she attacked him with two knives. Vargas said he and she fell to the floor, and he got a knife and stabbed her in self-defense.

Vargas had been living at Bermudez Leon’s house with his wife and their two young children. Vargas’s wife is Bermudez Leon’s daughter.

Vargas is in the country illegally and will be deported to his native Mexico after he completes his sentence, prosecutors said.