Several weeks before he massacred 49 at an Orlando gay nightclub, Muslim terrorist Omar Seddique Mateen transferred over his interest in his Florida home to his older sister and Afghan brother-in-law, property records show — an indication the family possibly had some knowledge of his martyrdom plans.

Authorities say the fatally shot Mateen clearly was prepared to die in a gun battle with police during the June 12 attack, the deadliest act of terrorism on U.S. soil since 9/11.

On April 5, Mateen “quit-claimed” the deed on his Port St. Lucie, Fla., house, signing it over to his sister, Sabrina Abasin, and his brother-in-law Mustafa Abasin according to county property records.  The records list his wife Noor Salman as a witness in the curious real estate transaction.

Mateen’s wife, who is expected to be charged as an accessory in her husband’s attack, reportedly has told authorities Mateen began casing targets as early as April. He was regularly training with firearms well before April.

Earlier this week, the mysterious brother-in-law — Mustafa Abasin, aka Mustafa Aurakzai — escorted the widowed Salman, who wore a hoodie to shield her face from cameras, to the Port St. Lucie home to collect belongings. Florida state records indicate he was born in Afghanistan.

The 43-year-old Abasin has been questioned by federal investigators. In fact, the entire family is under investigation. FBI agents have expanded the investigation overseas to include family connections in Afghanistan.

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