(CNN) -- Turkish authorities said they foiled an apparent bomb attack in Istanbul on Monday when they discovered plastic bags with explosives near a ticket stand.
Investigators detained one person at the scene and another after raiding a house where they found more explosives, said Muammer Guler, the governor of Istanbul.
Police were called to the stand, in a central area of the city, after witnesses saw several small plastic bags.
Officials cordoned off the area and shut down traffic. The bags were packed with 3.5 kg ( 7.7 lbs) of plastic explosives, but they did not explode, Guler said.
"Someone with plans to terrorize the city has been caught," he said.
Officials did not immediately disclose what the target may have been.
Sami Caylan, who works at the stand, said police arrested a man with a black backpack.
Police arrested a second man after raiding a house in the New Bosnia area of the city and finding more explosives and materials used to set off a bomb, Guler said.
Both men had invalid identification, he said, but officials did not immediately say if the men belonged to any particular organization.
Police were talking to a woman and a child who live at the residence, Guler said.
Militant Kurdish, leftist and Islamic groups have carried out several bombings in Turkey in recent years. E-mail to a friend
CNN's Talia Kayali contributed to this report
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