You're heading to a hostage exchange with your ex-girlfriend, who betrayed you at the beginning of the game and has been out to kill you ever since. You can't bring any weapons with you to the meeting.
A- Stow all of your weapons and ammunition nearby so you can get them again when you need them?
B- Throw away all of your weapons and ammunition so you won't have them anymore?
Thousands of grenades and molotov cocktails, tens of thousands of rounds of ammunition for other weapons, seventy some rockets, all gone.
(Update- It turns out that was the last mission, so I guess I understand why they wanted to take away all of my weapons. I think they could have come up with a better explanation for it though. I finished it by finding a couple more hidden packages to the get M-16 at my hideout so that I could finally finish the mission. I also used up my tank on the mission.
On a brighter note, I did kind of enjoy the mission where you have the rumble in the park and can only use a bat.