With protesters gathering outside and suspects throwing water and paint balloons at the property, the Cal Poly chapter of Lambda Chi Alpha has hired private security to stand guard at its frat house. [Mustang News]

Since a photo surfaced over the weekend of one of its members in blackface, Lambda Chi Alpha has been faced with backlash from the Cal Poly community. The university suspended the fraternity and launched an investigation into the blackface incident, and enraged students held a town hall meeting on Monday.

Also Monday evening, protesters marched to the Lambda Chi Alpha house, where they called for fraternity members to come outside and discuss the blackface incident. Later that night, four people in black hoodies were seen throwing balloons filled with water and black paint at the fraternity house.

San Luis Obispo police did not locate any of the suspects, though the individuals were caught on surveillance footage. Police were called to the Lambda Chi Alpha house four times on Monday.

As of Tuesday, a private security guard has been stationed outside the frat house. The guard confirmed he was hired by the fraternity, but he did not disclose any more information.

The blackface photo was taken during a Lambda Chi Alpha brotherhood event over the weekend. The fraternity has issued a statement apologizing for the incident and saying it was part of competition in which teams were represented by different colors, one of which was black.

Cal Poly’s Black Student Union and other angry students rejected Lambda Chi Alpha’s apology. Some protesters have called for fraternity members to be expelled from Cal Poly.