The raid happened on Bradford Road on Monday, May 18.
Officers found a handgun, ammunition and class A drugs.
A 51-year-old man was arrested on suspicion of possession of a firearm and possession with intent to supply controlled drugs.
The raid followed earlier police operations across West Yorkshire.
Police stopped a Skoda on Cannon Street in Castleford and found a pistol and ammunition in the car.
A 35-year-old man and 23-year-old man were arrested on suspicion of possession of a firearm with intent to endanger life.
A knife was found in a Golf which was stopped in the Chantry Bridge area of Wakefield.
Two men aged 43 and 29 were arrested on suspicion of possession of a firearm and an offensive weapon.
Later on, a man aged 20 was arrested on suspicion of possession of a firearm and possession with intent to supply controlled drugs.
Detective Chief Inspector Mark Walker said: "Our enquiries into these seizures remain ongoing and the six men remain in police custody.
"Illegal firearms and drugs can cause considerable harm and concern in the communities of West Yorkshire and beyond - through Programme Precision we are working together with key partners to bring those responsible for serious and organised crime to justice."
If you suspect crime in your community call police on 101 or give information online at www.westyorkshire.police.uk/101livechat or anonymously to the independent Crimestoppers charity on 0800 555 111.
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