Even before her boyfriend was named as the man responsible for the deadliest mass shooting in modern US history, Marilou Danley knew something was up.

An hour before Las Vegas cops released Stephen Paddock’s name, Danley deleted her Facebook account, according to newly released documents about the Oct. 1 mass murder of 58 people attending an outdoor country music concert on the Strip.

Danley was traveling in the Philippines when Paddock unleashed the bullet barrage from the 32nd floor of the Mandalay Bay resort.

When he was finally done with unleashing mayhem on thousands of innocents, he took his own life.

Danley was “adamant that she had no prior inclination of Paddock’s intentions to conduct the attack,” says an FBI agent’s affidavit.

But the documents suggest Danley moved quickly after the shooting to obscure her relationship with the 64-year-old Paddock.

Paddock began firing at around 10:08 p.m., according to emergency calls received by police.

At 2:46 a.m., her account was deleted, said the documents.

Authorities released Paddock’s name to the public at 3:30 a.m.