SAN JOSE (CBS SF) — Firefighters have contained a two-alarm grass fire that consumed between 5 and 7 acres of vegetation Sunday evening in San Jose, a fire captain said.

Fire crews responded to a report of a vegetation fire around 9:30 p.m. in the area of Curtner Avenue and Communications Hill Boulevard, a dispatcher said.

The fire was upgraded to a first alarm at 9:41 p.m. and to a second alarm at 9:48 p.m., San Jose fire Capt. Mike Van Elgort said.

Fire crews declared the fire “knocked down” at 10:39 p.m., he said.

“That means we have the fire completely surrounded and we’re in the process of completely extinguishing it,” Van Elgort said.

He said fire crews will likely be on scene all night to ensure the fire is completely extinguished.

The fire was threatening mobile homes on Chateau La Salle Drive but Van Elgort said no homes were damaged.

No injuries were reported, he said.

The fast-moving fire spread east to west up a steep hill and low-visibility conditions made the fire difficult to contain, Van Elgort said.

“The firefighters did a fine job of containing the fire,” Van Elgort said. “We used a combination of different strategies.”

Van Elgort said investigators won’t be able to determine the cause of the fire until dawn breaks.

“By the time fire crews got there, it had already spread an acre,” Van Elgort said. “It’s impossible to guess which way the fire was moving when it broke out.”

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