Three people involved in a "serious crime" and travelling in a Swedish-registered car are being hunted by Danish police.
A statement says the three are riding in a black Volvo V90, registration ZBP 546, and should not be approached.
"Witnesses who see the vehicle should contact the police immediately," the statement said.
Swedish newspaper Aftonbladet reports there has been a kidnapping, although police have not given further details.
Authorities closed off transport links to and from Denmark's largest island Zealand in their search. All of these links are now open or being reopened, police said.
The Great Belt Bridge, to the island of Funen, was wholly closed to cars, while ferries and trains were also affected.
Police armed with machine guns reportedly stopped a car on a motorway west of the capital Copenhagen (which is located on Zealand), according to a photographer quoted in newspaper Berlingske Tidende.
Dog patrols and a police helicopter are also reportedly near the scene.
The Italian people will end up worse off under the populist government's ambitious spending plans, the European Union has warned.
EU Economics Commissioner Pierre Moscovici said plans setting the budget deficit at 2.4% of GDP will only add to Italy's €2.3tn ($2.7tn; £2tn) debt.
But Italy's coalition government, which denies it is seeking conflict with Brussels, insists the debt will fall.
However, the budget announcement has sent tremors through the system.
Italian stocks fell almost 4% on Friday, while the euro slipped below $1.16 for the first time in two weeks.
How is Italy defying the EU?
Mr Moscovici said the European Commission had "no interest in a crisis" - words echoed by Italy's Deputy Prime Minister Luigi Di Maio.
However, Mr Moscovici added that Italy was "not respecting the rules" and reducing its "explosive" debt.
The budget decision is well short of the EU's deficit limit of 3% of GDP.
But Italy, the third-biggest economy in the eurozone, had promised to cut its debt decisively. The debt stands at 131% of national output, second only to Greece.