11:33 AM PT -- WKBW Buffalo just got video of Kodak leaving jail ... and covering his face with a big stack of cash. He kept quiet before piling into a minivan and driving off.

10:00 AM PT -- Kodak's show tonight in Connecticut at Foxwoods Resort Casino has been canceled. A rep tells us his show Friday night in Philadelphia will still happen.

9:12 AM PT -- Kodak has been released on $20,000 cash bond.

5:24 AM PT -- Cops say Kodak and 2 others attempted to enter the U.S. at the Lewiston-Queenston International Bridge in a Cadillac Escalade with a temporary California registration. They say Kodak was the driver, and officers discovered weed on him ... after further inspection of the vehicle they also found a Glock 9mm pistol which was undeclared by anyone in the Escalade.

There was also a Porsche traveling with Kodak's team with 3 other individuals. The driver of the Porsche copped to having 2 loaded handguns and a third was found in the trunk ... aaaand more marijuana. A law enforcement source described one of the weapons as an "AK-style handgun with a 30-round magazine. It looks like an AK, but it's a handgun."

Stetson President and Madarrow Smith were both arrested for criminal possession of a weapon ... Jeantony Saintmelus -- who was driving the Porsche -- was booked for criminal possession of a weapon and possession of marijuana.

While Kodak never made it to his show in Boston ... his tour bus did, and angry fans surrounded it after getting word he was a no-show.

4/18 3:27 AM PT -- It's now very clear why Kodak Black canceled his show in Boston ... the rapper was arrested on weapons and drugs charges at the U.S. Border. Law enforcement sources tell TMZ, Kodak and 3 other people were stopped by U.S. Customs Agents Wednesday. We're told Kodak was arrested for criminal possession of a weapon -- a felony -- and a misdemeanor possession of marijuana charge.

Multiple sources familiar with the arrest tell us Kodak was traveling with at least two guns ... and stopped when entering the U.S. from Canada.

The rapper is still in custody, being held on a $20,000 cash bond or $40,000 bond.

Kodak Black mysteriously canceled a concert last minute -- pissing off a ton of fans in the process -- and his team tells us his location and the reason for the cancellation is currently unknown.

Kodak was supposed to perform at The House of Blues in Boston Wednesday night but never showed. Fans waited for hours for the rapper before Kodak's team pulled the plug on the gig ... forcing local cops to have to assist in clearing the venue.

Here's where things get weird, we've spoken with several members of Kodak's team -- and everyone is telling us the same thing -- they don't know why the show was canceled and they can't get in touch with Kodak or those traveling with him.

What we know for sure, Kodak performed in Detroit Saturday night ... but at some point between then and Wednesday's show he's allegedly gone off the radar.

While it's highly unlikely his team just doesn't know where he is, or what happened, that's the story they've been sticking to for the last several hours.

Originally Published -- 4/17 8:32 PM PT