The Bulgarian Football Union (BFU) released a statement on Friday, confirming the arrest of a 20-year-old man.
It read: "Joint operational work of the interior ministry and the Bulgarian Football Union has led to an arrest for attempted manipulation of the national under-19 team matches.
"As a result of operational investigative actions, numerous individuals were questioned, including current under-19 internationals, who participated in the finals of the European Junior Championships in Hungary.
"These players are players of elite clubs from the top flight, which required information and assistance from their clubs.
"The Bulgarian Football Union would like to express its gratitude to those clubs to maintain the confidentiality and [to those who] cooperated fully in the investigation.
"We regret to note that the rapid actions had to be taken as a result, [which] probably influenced to some extent in purely psychological terms, the state of the national team during Euro 2014.
"The Bulgarian Football Union, however, is determined to do everything in their power to eradicate completely the manipulation of matches in the country."