Metallic and dark UFO appeared over Toronto

On October 14, 2014, a person took pictures during sunrise of the city of Toronto (in the province of Ontario). One of these photos of the CN Tower, it appeared a curious little object in the background…

Witness statement:

I was taking photos of the sunrise early in the morning. The location was on the 20th floor of an apartment building looking roughly NE approx. 15mi. towards the Toronto downtown skyline.

After taking several photos I noticed that 1 of them had an unusual silvery disk beside the CN Tower in Toronto. This is an area in downtown Toronto near to the Island (Billy Bishop) Airport. Small planes would fly by on a regular basis. After checking my photos taken of the skyline, this is the only image with the suspicious object.

However, given the shutter speed of 1/4s that was used, a plane flying would be recorded as a short line across the sky. The object that was captured appeared to be stationary. Was it a plane? an airship? I've never seen a weather balloon in this area so I don't think it was a balloon.

The first image was the original that came out of my digital camera with no computer touchup or enhancement. The second is a copy of the first with an arrow added to show where the suspicious object was. Since the object was only seen for such as short duration, there is a possibility the object may be a helicopter that remained stationary for a short time and then took off. At this point I don't want to jump into 1 conclusion until I get other opinions.