The Swiss nationals were kidnapped on Friday while travelling in impoverished and sparsely populated Baluchistan province, which borders both Iran and Afghanistan.
They were seized in Loralai district, 170 kilometres east of the provincial capital Quetta, provincial home secretary Zafarullah Baloch told AFP.
"We have launched an intense search. We have alerted police and paramilitary troops and we have also contacted tribal elders to help us locate the abductees," said Sohail-ur-Rehman, deputy commissioner of Loralai.
Loralai police chief Ghulam Ali Lashari said officers had found the couple's Volkswagen vehicle abandoned in Killi Nigah area.
The couple arrived at Sirki Jungle checkpoint at about 5:45pm on Friday, registered as Swiss tourists and were allowed to enter an area controlled by tribal police, Lashari said.
Officials quoting witnesses said "some unknown gunmen intercepted the Swiss couple when they were travelling in Killi Nigah area and took them away to an unknown place."
"Our priority is their safe recovery," Rehman said.
"We have no clues so far, we have received no demand, no ransom demand from the kidnappers."
Provincial home secretary Baloch said the search operation had been extended to three districts -- Loralai, Zhob and Qila Saifullah. Security had been increased on roads and tracks in these districts, he added.
"Our focus is Zhob" which borders Afghanistan and Pakistan's lawless tribal areas in the northwest, Rehman said.
Security forces were remaining vigilant to ensure the gunmen do not shift them to Afghanistan or the tribal areas, he said.
Officials said the pair had entered Baluchistan from Dera Ghazi Khan district in Punjab province and might have been heading for Quetta, perhaps on their way to Iran.
The Swiss foreign ministry on Saturday confirmed the kidnapping, saying that it is the first case of abductions of Swiss nationals in Pakistan.
The embassy in Islamabad "is in permanent contact with the local authorities, as well as its partners on the ground," said the ministry, adding that Swiss authorities are also in contact with the family members of the two abductees.
In addition, a taskforce has been set up to work towards "the liberation of the two hostages in good health."
Since 2008, Swiss authorities have advised its citizens against non-essential travel to the south Asian state, citing risks including the threat of kidnapping in Baluchistan, Sindh and south of Punjab.
Baluchistan has seen an upswing in violence recently, with the province suffering from a separatist insurgency, sectarian violence and Taliban militants.
Hundreds of people have died since rebels rose up in 2004 demanding political autonomy and a greater share of profits from the region's natural oil, gas and mineral resources.