(CNN) -- Darion Aguilar, who killed two people then himself at a Maryland mall last weekend, wrote in his personal journal about planning to kill people, Howard County police revealed Wednesday.
Aguilar also wrote that he was apologizing to his family "for what he was planning to do," according to police, who released information about what was in the journal. Aguilar wrote that he had a plan but did not explain what that plan was or mention whether it targeted anyone specifically.
Aguilar's mother told reporters Sunday that her son was a "gentle, sweet kid," and that she doesn't think he knew his victims -- 21-year-old Brianna Benlolo and 25-year-old Tyler Johnson.
Police say Aguilar went to the The Mall in Columbia on Saturday and fired as many as nine shots while in a skateboard apparel shop where Benlolo and Johnson worked.