I just picked this up from BBC News online.

Apparently, a US merchantman, namely ‘Global Patriot’ has fired upon a small vessel which approached it in the Suez canal. The small vessel was reportedly offering wares and may have failed to respond to a challenge from Global Patriot. Reportedly, one man on the small vessel has been killed while two others have been injured.

Global Patriot seems to be a large Ro-Ro operated by Global Container Lines, a US based shipping company.

To the best of my knowledge, US merchantmen are not armed with any naval guns or weaponry so I would guess that Global Patriot engaged the small vessel with small arms fire.

According to the BBC report, 100 other vessels have arrived at the scene demanding an inquiry. It is unclear at the time of writing whether Global Patriot remains at the scene. It is also not clear although seems likely that the small vessel was Egyptian in origin.

Update 0600: Some news outlets quoting Reuters are misidentifying Global Patriot as a ‘US Warship’.  The BBC report is also extended to add that Global Patriot was carrying US military supplies. The dead man from the small vessel is identified as Mohammed Fouad.