The Hatf (Hataf) program is Pakistan's short-range tactical missile project, developed using Chinese assistance. The Hatf-I is a single-stage, solid-fuel missile with a 60-80 km range, mounting a 500 kg payload. A lightened version could allegedly reach 350 km with a 100 kg payload. The 1989 Hatf-I was considered merely an experimental model (tests were halted after three unsuccessful flights) although a longer-ranged version (Hatf-1A) reaching 100 km and carrying a larger payload entered development in 1992, and was successfully tested in February 2000.
The Hatf-2 ("Shadoz") is a two-stage solid-propellant system, using two Hatf-1 stages stacked one on top of the other. Allegedly derived from the French Eridan sounding rocket, it had a range of 280 km with a 500 kg payload, or 450 km with a 300 kg payload. Developed in 1990 alongside the Hatf-1 program, it is believed to have been shelved due to problems with its guidance systems, and a new supply of M-11 missiles purchased from China, which offer almost the same performance.
The Hatf-3 is believed to be merely improved versions (M-11 Mod 2) of the M-11 missiles sold by China to Pakistan in 1997-1993, despite Indian claims that it is in fact, the longer-ranged M-9. Some reports state that over 80 M-11 Mod 2s are deployed at Sargodha Air Base. Several sanctions have been imposed on both Pakistan and China since 1993 for breaking the MTCR (Missile Technology Control Regime) annex; while China's sanctions were generally lifted soon after, those on Pakistan continued until they expired in 1995.
Part of the Chinese assistance allegedly includes building an M-11 missile production plant, started in 1995.
The Hatf-3 may not be a single missile system, but rather the designation for all current similar missile systems under deployment. The missile tested in July 1997 in response to India's deployment of Prithvi missiles on the border was most likely a M-11 Mod 2, although with unofficial sources claiming it was an 800-km missile, the Indian media believes it to be a longer-range M-9.
The Shaheen ("Shaheen" is a white royal hunting falcon) test (some sources call it the Hatf-4) in April 1999, a day after the Ghauri test, had a claimed 750-km range, consistent with the larger Chinese M-9, which may point to further, unknown missile deals between the two countries. Pakistani officials state it is able to carry a 1,000-kg payload. Two other Shaheen missiles displayed in a parade were confirmed to be the M-11 Mod 2, although photographs released to the Pakistani press were positively identified as the M-9 by both Indian and American analysts.
Data taken from www.fas.org.