House mice were accidentally introduced in the late 19th century.

This species is native to Europe, but has been accidentally introduced to many countries all over the world.

Although native to Europe, this species has been accidentally introduced to many other parts of the world.

Some species are kept as pets and have been accidentally introduced to various parts of the world.

Some of this brush was accidentally introduced from Europe or elsewhere.

Norway rats were accidentally introduced to the island in the 1980s.

It was first accidentally introduced to the United States in the 1960s.

There's absolutely no way the substance could have been introduced accidentally.

It has also been accidentally introduced to several other countries:

It is believed to have been accidentally introduced from Fiji.