The phrase "surprise assault" is correct and usable in written English.
It is typically used to describe a sudden attack or ambush, such as an unexpected military attack. For example, "The enemy troops launched a surprise assault on the unsuspecting village."
And after the initial surprise assault, government forces brought in heavy weapons to attack the rebels.
Republicans countered a Democratic bill with a surprise assault, arguing that the White House had told them it was unconstitutional.
Protesters sought to prevent any surprise assault by sleeping inside the tracks of the army's tanks and armoured vehicles.
It was ultimately overrun in a surprise assault on 21 September by Isis fighters in disguise, wearing Iraqi army uniforms and driving captured American Humvees.
The recapture of parts of Kunduz follows three days of heavy fighting after the Taliban seized the city in a surprise assault.
That is not how it is written up in the textbook, because it leaves the undercover officers vulnerable to a surprise assault.
But the police had suggested they would use a lighter hand this time, and allow a safe exit for the protesters, who numbered perhaps 5,000 at Cairo University and 10,000 in Nasr City.In the event, however, the security forces appear to have used a full panoply of force, launching surprise assaults on both protests with tear gas fired from helicopters, buckshot, sniper fire and automatic weapons.
The attack was part of the Tet Offensive in 1968, when North Vietnam launched surprise assaults on towns and cities across South Vietnam, with the support of its southern based guerrilla force, the Viet Cong.
Yet Cameron used his first prime minister's questions to mount a surprise frontal assault.
George H. Putnam remembered a contest among Union troops in Texas that was aborted by a surprise enemy assault.
In 1941, the Germans planned a surprise parachute assault to capture the island of Crete in the Mediterranean.
