Border guard data from October 2016 to September 2017 released by the interior ministry said over 3,500 weapons and stashes of ammunition were captured.
The statement said 4,656 suspects were arrested at the frontier in connection with attempted smuggling, “over half” of them from Yemen.
More than 2,311 tonnes of qat – a chewable narcotic leaf from Yemen that is banned in Saudi Arabia – were also seized, it said.
The release of the data comes the morning after Saudi air defence intercepted a missile fired at its territory by Yemen’s Iran-backed rebels.
The announcement came a day after British Prime Minister Theresa May said slammed Iran’s destabilising behaviour in the region during a visit to Riyadh yesterday where she met King Salman Bin Abdul Aziz and Crown Prince Mohammad Bin Salman.
Saudi Arabia accuses Iran of smuggling in weapons for Al Houthi militants.
Last month a ballistic missile fired by the militants targeted Riyadh but was intercepted. Saudi Arabia called the attack ‘an act of war’.
Saudi Arabia has intervened to help the Yemeni government after an Al Houthi coup in 2014 ousted the internationally-recognised president Ali Abdullah Saleh.
Riyadh accuses its arch-rival Iran of arming Yemen’s Al Houthis and the conflict in the country has ratcheted up tensions in the long-standing rivalry between the two regional titans.