Article: In 1970, the New Haven Black Panther trials took place, the largest and longest trials in Connecticut history. Black Panther Party co-founder Bobby Seale and ten other Party members were tried for murdering an alleged informant. Beginning on May Day, the city became a center of protest for 12,000 Panther supporters, college students, and New Left activists (including Jean Genet, Benjamin Spock, Abbie Hoffman, Jerry Rubin, and John Froines), who amassed on the New Haven Green, across the street from where the trials were being held. Violent confrontations between the demonstrators and the New Haven police occurred, and several bombs were set off in the area by radicals. The event became a rallying point for the New Left and critics of the Nixon Administration.

Now answer this question: What day marked the beginning of New Haven being overwhelmed by 12,000 individuals protesting the Black Panther trials?
May Day