An explosive device was found and detonated by authorities at Robert Crown Memorial State Beach on April 7, police said.

The device, which appeared to be some sort of firework, was found on the ground about 10:30 a.m. by a park worker carrying out maintainence near the restrooms at Shoreline Drive and Park Street, said Lt. Jon King of the East Bay Regional Park District.

Portions of the beach and the intersection were closed during the investigation. The bomb squad of the Alameda County Sheriff's Office responded to the scene and determined that the device was potentially explosive in nature. The device was safely detonated in place and no injuries were reported, King said.

"We're not exactly sure what it was, but it appears it was possibly some type of firework that was concealed," King said. "I understand it made a pretty loud sound when it was detonated."

Anyone with information about the incident is asked to call police at 510-881-1833.

THURSDAY, APRIL 4

  • BURGLARY -- A television was stolen after a burglar broke into a basement in the 1200 block of San Antonio Avenue. The burglary was reported at 8 a.m. A residential burglary was also reported about 12:15 p.m. in the 1000 block of Fair Oaks Avenue, while someone stole a GPS device and a FasTrak card from a vehicle parked in a garage in the 2200 block of Coral Sea Street in what police have classified as a burglary.

  • ANIMAL CRUELTY -- A woman, 59, who surrendered her cat to the city's animal shelter was cited for animal cruelty because its claws were growing into its paw pads, police said.

    FRIDAY, APRIL 5

  • VEHICLE THEFT -- A 19-year-old man who was spotted driving a vehicle reported stolen in Vacaville led officers on a brief foot chase after he was pulled over, police said. The man was arrested just after noon at Oak Street and Santa Clara Avenue.

  • ROBBERY -- Police arrested a man, 20, about 1:40 p.m. in the 2600 block of Broadway after he allegedly used a replica gun during an attempted robbery. The victim resisted the man's demand and no items were stolen.

    SATURDAY, APRIL 6

  • WEAPONS POSSESSION -- A man who threatened to take someone's life during an argument was arrested just before 7 p.m. at Park and Central avenues, where officers allegedly found a loaded handgun in plain sight in his vehicle. The firearm's serial number was obliterated, police said. The 29-year-old man, who was also allegedly in possession of less than one ounce of marijuana, faces multiple felony charges, police said.

    SUNDAY, APRIL 7

  • DRUNKEN DRIVING -- Police arrested a man, 27, on suspicion of drunken driving after a traffic stop at 2 a.m. at Park Street and Eagle Avenue. The man also faces a charge of driving without a license.

    MONDAY, APRIL 8

  • VEHICLE THEFT -- A vehicle was reported stolen at 9:25 a.m. in the 1700 block of Chestnut Street. A vehicle was also reported stolen about 12:30 p.m. in the 500 block of Buena Vista Avenue.

  • PETTY THEFT -- Police arrested a man, 51, on suspicion of petty theft after security at Kohl's at Alameda South Shore Center said he shoplifted merchandise. The arrest occurred about 2:45 p.m.

  • BURGLARY -- The burglary of a garage in the 100 block of Santa Clara Avenue was reported at 7:40 p.m.

  • MARIJUANA POSSESSION -- A motorist who a patrol officer pulled over for a traffic violation was arrested after a background check revealed that he was wanted on an outstanding warrant. Officers also found less than one ounce of marijuana while searching the 24-year-old man and the vehicle, police said. The arrest occurred about 10:30 p.m. in the 2400 block of Otis Drive.

    TUESDAY, APRIL 9

  • MARIJUANA POSSESSION -- A traffic stop about 12:10 a.m. in the 1500 block of Park Street led to the arrest of an 18-year-old man after he was found in possession of less than one ounce of marijuana, police said.