Violence broke out this week in Nogales, Sonora, culminating on Wednesday with a mysterious attack by armed men on a home near Calle Pirinola in mid-town Nogales.

Police and military personnel investigate the scene on Calle Pirinola after a home was riddled with bullets and gunmen left behind a live grenade in Nogales, Sonora. Photo / Cesar Barron

The assailants shot up the house and lobbed a hand grenade that, fortunately for bystanders, did not explode.

The home is in the Empalme-Nogales neighborhood. The attackers abandoned a late-model Chevrolet Tahoe after it became stuck during the incident. Inside the vehicle was a portable radio and on the ground next to the Tahoe was a cap with the insignia of the Federal Investigations Agency (AFI).

Shortly after 1 p.m. police received reports of gunshots. Local and state lawmen arrived at the scene shortly thereafter along with troops from the Mexican Army. They found the Tahoe near the bullet-riddled home. A few feet away, a live grenade was on the ground. A special military bomb squad was called in to remove the explosive device.

There were no reports of injuries from the shooting.  

Meanwhile, two unidentified men in the early to mid-30s were shot with AK-47s and killed on Tuesday as they slept in a hotel room on the south side of town. Other gun battles were reported throughout the city.

Elsewhere in Sonora, grenade attacks occurred in Navojoa, Hermosillo and Cananea.

In Cananea, about 50 miles by road southeast of Nogales, a hotel maintenance man opened a door to a room that had been booby-trapped. He sustained life-threatening injuries and was taken to a hospital in Hermosillo, according to Nuevo Dia newspaper.

On Monday at a Cananea gasoline station, a man drove up in a late-model vehicle and requested 200 pesos worth of fuel. The car apparently also was booby-trapped. The man left and when an attendant went to open the car door, the vehicle exploded.

Nuevo Dia reported that the attendant was injured and is in guarded condition. Investigators found a dozen more grenades in the back seat of the vehicle.

There were explosions also reported at two banks in town.

Drug traffic cartels are known to use grenades in battles with their rivals and police, but there was no official indication that the attacks were linked to the drug violence that has plagued Mexico.

(Compiled by staff, from Mexico newspaper reports and Radio XENY in Nogales Sonora.)