A Santa Rosa man accused of selling fentanyl-laced cocaine to local high school students who died over the weekend appeared in court Tuesday but has not been formally charged in their deaths.

Drug overdoses took a deadly toll in Santa Rosa over the weekend. Police are investigating the deaths of four young people, and the hospitalization of two more, to see if they are connected to a man arrested for selling narcotics,

A cluster of accidental drug overdoses have left students at two Santa Rosa schools mourning the deaths of their classmates this week. Police said two teenagers died, and two more were hospitalized. Detectives suspect that the four victims bought fentanyl-laced cocaine from the same drug dealer.

As police investigate, key details have emerged about the events leading up to their deaths — but questions remain.