Authorities in the western German city of Herne have called in experts to catch a monocled cobra that is still on the loose, despite a multi-day effort to capture the reptile.

The 1.4 meter-long (4.6 foot-long) venomous snake was found in the stairwell of an apartment building on Sunday, prompting police to evacuate 30 residents from the building and neighboring houses as well.

Local police said they believe the snake is still in the building where it was found.

Animal experts sprinkled flour around the house in the hopes the snake would leave a trail they could follow and capture it. They even put double-sided sticky tape on the ground in an attempt to track the reptile down.

The city believes the snake escaped from an enclosure in one man's apartment where authorities found 20 other venomous snakes.

The man has since been barred from keeping snakes, although he claims the missing cobra did not come from his collection.

Record-breaking snakes The most venomous snake The inland taipan produces the most toxic venom in the snake kingdom. Researchers estimate that one bite could kill more than 100 men. The taipan's venom is specially adapted to kill warm-blooded animals. It affects the nervous system, the blood and the muscles. The species lives in semi-arid regions in Australia and is strictly protected.

Record-breaking snakes The deadliest snake Though its venom only kills one out of 10 untreated people, the aggressiveness of this snake means it bites quickly and often. This is why the saw-scaled viper is considered the world's deadliest snake, killing the most people. Venomous snakes have diamond-shaped pupils, like cats. Non-venomous snakes have round pupils, like humans. But remember: there is no rule without exceptions!

Record-breaking snakes The largest snake The green anaconda is the largest snake in the world. Living in the dark, deep waters of the South American jungle, some anacondas have been reported to be up to 8.8 meters (29 feet) long. The average anaconda is only about 4 meters long. They are very robust snakes and packed with muscles which they use to kill their prey by wrapping around it and slowly suffocating it.

Record-breaking snakes Even larger The green anaconda is nothing compared to the titanoboa. This pre-historic snake was a true giant. The photo shows a python creeping over a single vertebra of titanoboa cerrejonensis discovered in Colombia. Fossils suggest titanoboas could grow up to 13 meters long and weigh 1,135 kilograms (2502 pounds). Like the green anaconda, they probably lived in or very close to water, 40 million years ago.

Record-breaking snakes The smallest snake The Barbados threadsnake is about 10 centimeters long and, according to its discoverer "about as wide as a spaghetti noodle." It feeds on termites and ant larvae and is found only on the Caribbean island of Barbados. S. Blair Hedges, a herpetologist from Pennsylvania State University, discovered the species in 2008.

Record-breaking snakes The greediest snake Snakes have a flexible lower jaw that enables them to swallow animals twice their own size. But sometimes even that is too much for them. In 2005, in the Everglades National Park in Florida, a python exploded after trying to swallow a whole alligator. The snake was found with the alligator's tail sticking out of its midsection. Seems like someone got a bit greedy.

Record-breaking snakes A master of camouflage Just a leaf? No, it's a gaboon viper. The form and color of its head resembles a leaf perfectly, enabling the ambush predator to wait patiently for prey coming by in the African rainforests. It has the longest fangs of all snakes - up to 5 centimeters (2 inches) - and is also very venomous. The snake is not at all aggressive, though. Only very few people are bitten by it.

Record-breaking snakes The sneakiest snake This guy, the scarlet kingsnake, is non-venomous. But it doesn't want other animals to know that. So it mimics the venomous coral snake which has the same tricolored pattern of black, red and white. It's a sneaky way to tell predators to get lost.

Record-breaking snakes Most water-loving snake Snakes are everywhere - you can even find them at a coral reef. Some of those sea snakes are really venomous. Unlike fish, they do not have gills and need to get up to the surface regularly to breathe. Sea snakes can grow up to 3 meters (9.8 feet), but the majority only grows up to 1.5 meters. This species, the banded sea snake, regularly returns to land to digest its food, rest and reproduce.

Record-breaking snakes Snakes that fly This snake can propel itself forward by thrusting its body up and away from a tree. That's why it is commonly known as the "flying snake." It curls itself up to resemble the form of a frisbee and glide up to 30 meters wide from tree to tree. Its biological name is Chrysopelea and it feeds on lizards, rodents, birds and even bats. But it's harmless to humans. Author: Brigitte Osterath, Sophia Wagner



Debate over exotic pet rules

The search for the cobra has made headlines across Germany and sparked calls for stricter regulations on people who keep exotic animals as pets.

"I am personally against keeping very dangerous species in apartments or homes," Ursula Heinen-Esser, the environment minister for the state of North Rhine-Westphalia where Herne is located, told news agency dpa.

She added that she "doubts that keeping such animals in apartments is species-appropriate or humane."

As long as owners adhere to species protection rules, there are very few regulations in Germany about keeping wild animals in private households.

In 2014, state lawmakers in North Rhine-Westphalia tried to push through a law that would have banned people from keeping highly dangerous animals like venomous snakes, crocodiles, scorpions or big cats in their homes. The law received pushback from municipal authorities and never came into effect.

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rs, kw/ng (AP, dpa)