Federal prosecutors said on Tuesday (Jan 6) that they had released transcripts of video recordings in which the man responsible for last month’s deadly shooting at Brown University acknowledged planning the attack months in advance before later taking his own life. According to prosecutors, four videos made by the suspect, Claudio Neves Valente, were discovered inside a storage unit in Salem, New Hampshire. Valente was found dead there on Dec 18 from a self-inflicted gunshot wound, bringing an end to a six-day manhunt.

Valente, 48, a Portuguese national and former Brown University doctoral student in physics, entered an engineering building on the campus on Dec 13 and opened fire with a handgun, killing two students and wounding nine others, police said. After fleeing the scene in Providence, Rhode Island, authorities determined that he later killed an MIT physics professor at the professor’s home near Boston in a separate attack.

Investigators revealed that Valente and the slain MIT professor, Nuno Loureiro, had been classmates years earlier in Lisbon, though a motive for either shooting has not yet been established. The newly released transcripts, obtained by the FBI from an electronic device and translated from Portuguese, are the first statements attributed to Valente since his death. While they confirm long-term planning of the Brown University shooting, they provide little additional insight into the reasons behind the violence.

In the recordings, which prosecutors described as disorganized and rambling, Valente said he had been planning the attack for more than six academic semesters. He spoke vaguely about events without directly mentioning firing a weapon or killing anyone and offered no explanation for what led to the violence. He expressed no remorse, stating that he did not regret his actions and refused to apologize, citing grievances he felt were never acknowledged during his life. Prosecutors said the investigation has found no indication of any ongoing public safety threat connected to the shootings, though efforts to determine Valente’s motive are continuing.