Armed men raided the house of the aid worker on Friday, killing his two guards before driving him off across the desert, the mayor of the town of Abalak said on Saturday.
“First they came on a motorbike and killed the guards,” the mayor told Reuters news agency by phone. “Then a 4×4 came and took him away and drove towards the Mali border.”
Niger’s long, porous borders make it occasionally vulnerable to the armed violence that has rocked neighbouring states including Mali in recent years.
Northern Mali, which fell under the control of al-Qaeda-linked groups in 2012 before a French-led military intervention pushed them out, remains vulnerable to attacks by fighters.
“At least two people were killed during an exchange of gunfire” as the hostage was being taken, a security source who wishes not to be named told AFP news agency, without revealing the identity of the victims.
“All roads to Mali are being monitored.”
It is the first time that a US national has been kidnapped in Niger.