The present invention relates to a device for closing an open, bleeding wound of an animal or human body. The invention further relates to a device for processing tissue of a human or animal body, for example, a device for producing a support in a vessel of the body. The device for closing a bleeding wound firstly comprises a laser for irradiating the blood in the wound with infrared laser radiation. According to the invention, the laser radiation of the laser can be adjusted such that two- or multiphoton absorption occurs in irradiated regions of the blood, whereby the blood in the irradiated regions polymerises into a solidified biopolymer and closes the wound.
