The co-leader of the far-right Alternative for Germany (AfD) party Tino Chrupalla has been brought to hospital after appearing at a campaign rally in the southern German city of Ingolstadt, four days ahead of state elections in Bavaria.
Police said Chrupalla received medical treatment ahead of a speech in Ingolstadt on Wednesday afternoon, before he was brought to hospital.
An obvious injury had not been immediately apparent at that time, police said.
"In order to clarify the more detailed circumstances of this medical incident, further investigations have been taken over by the Ingolstadt Criminal Investigation Department," the statement continued.
A police spokesman said an investigation would look into whether a third party was potentially responsible for the incident. However, there was currently no indication of an attack, he said.
The AfD's national office said Chrupalla was hospitalized following a "violent incident" at the rally.
According to a spokesman for the AfD's Bavarian parliamentary group, the incident occurred in the crowd just before the party leader was scheduled to speak.
Police called on witnesses to provide any photo or video footage from the event.
The AfD campaign rally in Bavaria came just days ahead of state elections, scheduled for Sunday.
Chrupalla, 48, has been co-leading the AfD for almost four years. His current co-leader is Alice Weidel.
The AfD was founded by eurosceptics a decade ago. It has since become more radical, particularly in its stridently anti-immigration positions. AfD party branches in several German states, including in Bavaria, are monitored by Germany's domestic intelligence agency as potential right-wing extremist groups.
Recent polls put support for the AfD at between 12% and 14% in Bavaria and while it is not expected to have much influence over the shape of future government in the state, with the party polling at over 20% nationwide the AfD's support among Bavarian voters may prove one of the most significant aspects of Sunday's elections.
