The second attack targeted a chrome mining business in Kirklare, police said. The company's building and six of its trucks were burned before the attackers left with several employees.
A village in the same district had been attacked earlier by gunmen who fired Kalashnikovs at houses and left without inflicting any injuries, Hurriyet Daily News reported.
Investigators were unsure of the identity of the attackers. The outlawed Kurdistan Workers Party, usually known by its Turkish acronym PKK, is active in the area.
A construction supervisor working on a military station was kidnapped Tuesday in Tunceli, police said. His burned-out pickup truck was discovered Wednesday.
The kidnappers were believed to be members of the PKK, the Dogan news agency reported.
In another attack Tuesday night in Erzerum province, also in eastern Turkey, a heavy construction vehicle and four trucks were burned.