When hot-headed subway riders attack other commuters, they use umbrellas, swords, keys, and even crates, police said Monday.

Felony assaults have risen almost 27% in transit this year, through the end of August, according to the NYPD.

"It's bad behavior. It's two people in a crowded place bumping into each other, and one actor becoming violent," said Transit Bureau Chief Joseph Fox. "And look at the type of weapons. It's not like someone carried an umbrella with the intention of assaulting someone, it was handy."

During two rainy days in June, riders clashed with other straphangers and assaulted them with umbrellas.

John Damico, 42, was arrested for giving an acquaintance six stitches when he allegedly assaulted him with an umbrella on a downtown No. 4 approaching the East 59th Street subway station in Manhattan on June 27, according to police officials.

Three teens were also arrested for attacking another teen with an umbrella at the Borough Hall station in Brooklyn.

Other objects used in recent assualts were even wackier:

On Aug. 29, a rider donning a red costume and wooden sword was assaulted by a rider who broke the sword and then hit him with it.

A commuter hit a woman at the Prince Street station in Manhattan with a grape soda in the back of her neck on the platform after cursing at her on Aug. 11.

Another woman was assaulted by a rider's hard hat at 42nd Street-Port Authority station, officials said.

Despite the bizarre attacks, the NYPD has seized more traditional weapons -- guns -- than last year in the subway system.

Almost 30 illegal guns have been seized this year, up from 17 over the same period. Eight have been taken out of the subway by transit cops since August 1.

The most recent include Jack Jervis, 24, who was busted by Police officers Claude Montout and Leonel Pena in Union Square at 12:30 a.m. for a 32-caliber gun, according to the NYPD. He was charged with weapon and pot possession.

Cops have also seen an increase in the number of sleeping riders targeted by thieves.

They made up almost a third of crime victims- -- up from 10% in 2009.

"Between electronic thefts and sleeping passengers, half of our daily 6.4 crimes is accounted for," added Fox.