(CN) – Rafia Sultana Shareef did not know her son and his wife would carry out a mass shooting – a deadly act of terror – the last time she saw them on the morning of Dec. 2, 2015.
On Monday, she pleaded guilty to destroying a handwritten map found in her son’s bedroom after she found out he was identified as a suspect in the San Bernardino, California, shooting.
The couple – Syed Rizwan Farook and his wife Tashfeen Malik – killed 14 and physically wounded 22 others at a county building where they opened fire with high-powered rifles during a holiday party.
The couple left their infant child with Shareef that morning when they said they were going to a medical appointment, according to federal prosecutors who announced Monday that Shareef had pleaded guilty to a charge of destroying evidence related to the shooting.
On the day of the shooting, Shareef learned her son was a suspect and according to the plea agreement, she told other family members she thought he carried out the shooting with Malik.
Federal prosecutors say that before she left the Redlands, California, home she shared with Malik and Farook at 3:41 p.m., Shareef put the map in a shredder.
Malik and Farook shot at people inside and outside the Inland Regional Center, including Farook’s co-workers attending the holiday party. Farook also brought a bag of explosives to the site before the shooting attack began, according to federal prosecutors.
The handwritten map destroyed by Shareef was “probative of the attack” and was destroyed to “impede, obstruct, and influence the criminal investigation” against Farook and Malik, according to the plea agreement.
Prosecutors say Shareef, now 66, did not have prior knowledge of the attack carried out by her son and his wife.
Federal investigators have classified the San Bernardino shooting an act of terrorism because Farook and Malike were influenced by the Islamic State Group.
Shareef, aka Rafia Sharook, will make her initial appearance later this month and could face up to 20 years for intending to impede a federal criminal investigation, prosecutors said.