Oseney da Costa Oliveira, 41, has been held in Brazil as the search for the British journalist drew to a close after his brother Amarildo da Costa Oliveira, was arrested earlier last week.
It comes hours after the brothers accused of killing and dismembering Phillips and his Brazilian guide were pictured in handcuffs as police led them to the area where the bodies may have been dumped
Human remains have been found in the search for a British journalist and Brazilian indigenous expert who disappeared deep in the Amazon after receiving threats, Brazil's president confirmed Monday.
Relatives of veteran correspondent Dom Phillips and respected indigenous specialist Bruno Pereira meanwhile said authorities informed them two bodies had been found, though police and local indigenous leaders denied that, adding to confusion around the case.