President Donald Trump has suspended the US green card lottery scheme in the wake of a mass shooting at Brown University last week in which two people were killed.

The suspect, a Portuguese man found dead on Thursday, entered the country through the diversity lottery immigrant visa program (DV1) in 2017 and was subsequently granted a green card.

Homeland Security Secretary Kristi Noem stated she has paused the visa scheme under Trump's direction to ensure no more Americans are harmed by this disastrous programme.

US officials believe the suspect, 48-year-old Claudio Neves Valente, also killed MIT professor Nuno Loureiro earlier in the week.

The program issues up to 50,000 visas each year through a random selection process aimed at individuals from countries with low immigration rates to the US. Noem noted that Trump had previously sought to end the scheme back in 2017, following another attack where a DV1 recipient was involved.

Valente was suspected in two shootings, one being at Brown University where two students lost their lives during final exams.

Both students, identified as 19-year-old Ella Cook and 18-year-old Mukhammad Aziz Umurzokov, have been mourned by the university community. Authorities are still investigating the motive behind the shootings.