Security authorities in Beheira Governorate arrested four Libyans in possession of weapons Thursday at a checkpoint on the Wadi al-Natrun desert highway, according to a security source.
Those arrested are Libyan nationals who reside in Benghazi, the statement added.
Security found 31 pistols and 14 copper bars in the car. The arrested confessed that they planned to traffic the items, said the source.
The Public Prosecution has begun an investigation into the incident.
Egypt has witnessed an increase in weapon smuggling since the 25 January revolution that ousted former President Hosni Mubarak.
Authorities announced in June that they had confiscated a two-meter rocket launcher, 101 rockets, 48 missiles, 12,225 bullets and four automatic guns in Beheira Governorate.
Egyptian media have reported a rise in arms smuggling across the Libyan border since late leader Muammar Qadhafi was toppled in Libya's uprising last October.
A senior Israeli official said in July that Libya had become a new source of weapons for the Gaza Strip, which is run by Israel's Islamist foe, Hamas.
Edited translation from MENA