Petr Zelenka is a Czech

Czech Republic

The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....

 serial killer

Serial killer

A serial killer, as typically defined, is an individual who has murdered three or more people over a period of more than a month, with down time between the murders, and whose motivation for killing is usually based on psychological gratification...

. Zelenka, a nurse in Havlíčkův Brod

Havlíckuv Brod

Havlíčkův Brod , Německý Brod until 1945 is a town in the Vysočina Region of the Czech Republic. It is also the capital of the Havlíčkův Brod district. It is located on the Sázava River in the Bohemian-Moravian Highlands and has a population of 24,321 as of 2003...

, 100 kilometres (62.1 mi) southeast of Prague

Prague

Prague is the capital and largest city of the Czech Republic. Situated in the north-west of the country on the Vltava river, the city is home to about 1.3 million people, while its metropolitan area is estimated to have a population of over 2.3 million...

, murdered seven patients by lethal injection

Lethal injection

Lethal injection is the practice of injecting a person with a fatal dose of drugs for the express purpose of causing the immediate death of the subject. The main application for this procedure is capital punishment, but the term may also be applied in a broad sense to euthanasia and suicide...

, and attempted to kill 10 others between May and December, 2006. He killed with a hidden vial of heparin

Heparin

Heparin , also known as unfractionated heparin, a highly sulfated glycosaminoglycan, is widely used as an injectable anticoagulant, and has the highest negative charge density of any known biological molecule...

 — a blood-thinning drug causing internal bleeding

Internal bleeding

Internal bleeding is bleeding occurring inside the body. It can be a serious medical emergency depending on where it occurs , and can potentially cause death and cardiac arrest if proper medical treatment is not received quickly....

 when administered in large doses. Zelenka has already confessed and been taken into custody. His lawyer has been quoted as saying that Zelenka may have killed on an impulse to "test" doctors in Havlíčkův Brod, in the belief they were not good enough to discover the truth. In February 2008, Zelenka was convicted of killing seven patients and attempting to kill 10 others, and sentenced for life

Life imprisonment

Life imprisonment is a sentence of imprisonment for a serious crime under which the convicted person is to remain in jail for the rest of his or her life...

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