A top commander of the Afghan insurgent Jalil Haqqani of the Haqqani network was among at least 10 killed in separate US drone strikes in Pakistan's tribal northwest on Thursday.

According to the Times of India, the strikes coincided with special US envoy Marc Grossman's visit to Islamabad to improve bilateral ties soured after Washington accused the ISI of supporting Haqqani network attacks in Afghanistan.

The US has put significant pressure on Islamabad to destroy the Haqqani networks safe havens in the region following last month's attack on its embassy in Kabul.

But Pakistan's top generals have been reticent to do so fearing a major offensive would draw too many forces from other regions, including the disputed Kashmir region on its border with rival India.

Pakistani officials say the first drone strike killed the network's logistics commander Jalil Haqqani along with three others at Dande Darpa Khel in their stronghold of North Waziristan.

The men, the officials said, were walking down a street when they were killed by an air-to-ground missile. Jalil is said to be related to the group leader Sirajuddin Haqqani.

Hours later, another drone strike killed seven insurgents and injured four at Bermal in South Waziristan. Officials said they were killed while firing rockets and mortars across the border at an American military base in Afghanistan.

US officials have maintained that the insurgent group uses the lawless tribal region to launch attacks on coalition forces and US targets in Afghanistan. The network is one of most organized insurgent terror factions fighting the US in Afghanistan.

The US has regularly relied on drones to target terrorists in the tribal region since 2008. It has launched around 50 drone strikes mostly in North Waziristan this year.

Meanwhile, Grossman met PM Yousaf Raza Gilani, president Asif Ali Zardari and army chief general Ashfaq Pervez Kayani and discussed US concerns about the network.

The US has indicated that it was open to talks with the Haqqanis, which observers say is likely Grossman's main assignment in Islamabad.