The police initially escorted the group, who were heading to the Hungarian capital after leaving a migrant camp on the border.
At Roszke, on Hungary’s frontier with Serbia, around 300 migrants broke through a cordon around a reception camp and set off down the wrong side of the motorway towards the capital Budapest, Reuters witnesses said.
Police were unable to prevent their escape despite using pepper spray as migrants scuffled with officers.
On the highway, the group complained the police were preventing them continuing their journey.
“Just, we want to walk. Let us going, let us walking,” said one man from Damascus.
“There are people who are sick, it’s extremely cold over there. They are giving us the minimum amount of food and we don’t want their food. We just want to cross the borders. We’re not demanding anything, we don’t want to be put in hotels. We just want to cross the border and get to the country we’re destined to go to. Germany is accepting all of us. Why don’t they just let us go?” said another, also from the Syrian capital.
Germany has announced it is letting Syrians seek asylum regardless of where they enter the EU, suspending normal rules and accelerating a flow of migrants north and west from the edges of the bloc.
Just last month, more than 100,000 asylum seekers reached Germany, which is preparing for 800,000 this year, around one percent of its population, a move with little precedent for a large Western country.