The phrase "army encountered" is correct and usable in written English.
It can be used in contexts discussing military operations, historical events, or encounters between armed forces.
Example: "During the campaign, the army encountered several unexpected challenges that tested their resolve."
Alternatives: "military faced" or "troops met".
On 3 February the Allied army encountered the main Argentine force commanded by Rosas himself.
The Mongol army encountered the Bulgars in another battle in which they routed the Bulgars.
The city was besieged by the end of the month, after Madero's army encountered some resistance in the Chihuahuan countryside.
The British army encountered an extremely hostile population, prepared to resist to the degree that even women, children and slaves voluntarily participated in the defense.
The French colonial army encountered strong resistance from Ahmed al-Hiba, a son of Sheikh Ma al-'Aynayn, who arrived from the Sahara accompanied by his nomadic Reguibat tribal warriors.
And then the Danish army encountered the ships from East Anglia and from London, and they made a great slaughter there and captured the ship, all armed and equipped, on which the ealdorman was.. Scandinavians led by Óláfr Tryggvason had been raiding England's coast since the previous year, when they killed Ealdorman Brihtnoth of Essex at the Battle of Maldon.
Despite their significant military advantage the allied armies encountered immediate setbacks.
During the First Crusade (1096 1099) the Frankish armies encountered walled settlements and forts that they indiscriminately referred to as castles, but which would not be considered as such under the modern definition.
But in North and South Waziristan, the army has encountered fierce resistance from local tribesmen, assisted perhaps by a surviving handful of foreign jihadists.
In northern Lebanon, a plan for local groups to hand their weapons to the army has encountered some resistance because pro-government groups, which are a majority in the north, fear being left at the mercy of Hezbollah, said Misbah Ahdab, a member of Parliament from Tripoli.
The army troops encountered few Japanese but were greatly slowed by difficult terrain and stopped short of the coast for the night.
