The 18-year-old suspect in the Buffalo, New York, grocery store mass shooting is expected to make a second court appearance Thursday.

Payton Gendron is charged with killing 10 people and wounded three others last Saturday at a grocery store in a predominantly Black neighborhood. Eleven of those shot were Black.

The FBI is investigating the attack as a hate crime. U.S. President Joe Biden visited the scene Tuesday.

Investigators are studying a racist 180-page document, purportedly written by Gendron, that said the assault was intended to terrorize all non-white, non-Christian people and get them to leave the United States.

In his first court appearance, Gendron’s court-appointed lawyer entered a plea of “not guilty” on his behalf. The Washington Post reports New York law gives a defendant held after a felony arrest the right to a hearing unless he is indicted quickly, generally within five days.

If prosecutors from the Erie County District Attorney’s Office report Thursday that a grand jury has already indicted Gendron, no hearing will be necessary. If not, the judge may hear evidence to decide whether Gendron can remain in the county lockup, where he has been held without bail since his arraignment hours after the shooting.

Some information in this report was provided by the Associated Press.