PLEASANTON (CBS SF) — Police in Pleasanton are investigating an attempted robbery at a jewelry store Monday where a group of suspects armed with pepper spray and hammers tried to break into glass display cases, authorities said.

According to Pleasanton police, the seven male suspects — all wearing masks or hoodies — entered the Diamond Ring Company at Stoneridge Shopping Center in Pleasanton on Monday, November 13 at  8:19 p.m.

READ MORE: Sunnyvale Police Arrest Man Suspected of Homicide Following Fight With an Associate

The suspects entered the store and sprayed pepper spray towards the employees to distract and subdue them, police said.

READ MORE: Evacuations Ordered as Wildfire Burns in Butte County North of Chico

The suspects then made unsuccessful efforts to break the glass-enclosed display cases with hammers, realizing the glass was shatter proof.

After failing to break into the jewelry display cases, the suspects fled. Two dark colored sedans associated with the suspects were seen leaving the area.

MORE NEWS: Cruz Reynoso, First Latino California Supreme Court Justice, Dies at 90

Pleasanton police are asking that anyone who has any information about the suspects or suspect vehicles involved in the attempted robbery get in touch with authorities.