A small southern Dutch town has been put on high alert after a deadly cobra escaped, prompting authorities to urge residents to keep their windows closed and their children inside.

The Drimmelen municipality issued a general alert after a highly-venomous Cape cobra disappeared from a terrarium of a local collector in the nearby hamlet of Made, near the southern city of Breda.

The reptile, which has a reputation for easily striking out when threatened, was last seen on Wednesday.

"The cobra has fangs and a single bite can be deadly to humans," the Drimmelen municipality warned on its website.

"Residents in the area have been advised to keep their doors and windows shut. Parents are advised not to let their children play outside, but to escort them inside at once," a statement said.

Two reptile experts were at the scene and conducting a snake-hunt, a town official told the NOS public broadcaster on Friday.

There are no deadly indigenous snakes in the Netherlands and only the rarely encountered common viper has a poisonous bite.

Cape cobras are found mainly in southwestern South Africa and has a potentially deadly neurotoxic venom that requires immediate treatment with an anti-venom.

The snake is considered nervous and aggressive and will rise up, spreading its hood before readily striking at anything it considers to be a threat.