Siliguri, Feb. 10 :    Siliguri, Feb. 10:  The spearhead of the Gorkhaland movement, Subash Ghising, was shot at and wounded in the head in an ambush near Kurseong this evening. Two of Ghising's security guards were killed while six were injured when unidentified gunmen stopped his convoy and sprayed bullets. Police suspect militants to be behind the strike. The government has ordered a high-level inquiry into the incident. Chief minister Buddhadeb Bhattacharjee, who described the attack as 'dastardly', directed the police to take 'immediate steps' to arrest those involved. The Gorkha National Liberation Front (GNLF), which Ghising heads, has called an indefinite strike in the hills from tomorrow. Ghising, who is admitted to a private nursing home in Siliguri, will be taken to New Delhi's AIIMS tomorrow in a chartered aircraft. Ghising was on his way back to Darjeeling after attending the first round of the tripartite meeting between representatives of the Darjeeling Gorkha Hill Council (DGHC), the state government and the Centre on reviewing the Gorkha Hill Accord. This is the first attempt on Ghising since he launched the movement for a separate state in the early eighties. Doctors said the GNLF chief was still not out of danger and his condition will have to be monitored for the next 48 hours. Darjeeling chief medical officer of health Tarak Nath Chhatoraj said: 'His condition is stable and he is now conscious. Neuro-surgeons are operating on him to extract shrapnel lodged just behind his right ear. It is more of a superficial injury.' Additional superintendent of police (headquarters) Javed Samim said: 'Unidentified gunmen ambushed the five-car convoy of the GNLF president at Chilauney-dhura near Sat-ghoomti between Garidhura and Kurseong on the Pankhabari Road around 6 pm. The suspected militants lobbed a grenade at Ghising's Ambassador and sprayed bullets from both sides of the road. They took advantage of the thick forest cover in the area. While four vehicles were damaged, the assailants set on fire the pilot car.' The attackers, armed with sophisticated weapons, kept up a 30-minute exchange of fire with the Greyhound commando force assigned to guard the GNLF chief. One of the assailants was killed in the return fire by security personnel. An AK-47 rifle and a mobile phone were recovered from the spot. Securitymen whisked away the injured Ghising to an undisclosed place before bringing him to the nursing home here under heavy security cover. Entry to the clinic has been restricted. Tension gripped the hills of Darjeeling as news of the attack spread. Leaders of the GNLF's branch units, who met tonight, alleged that the ambush was a 'pre-planned conspiracy'. They wondered how the Darjeeling district magistrate, the superintendent of police and the additional SP in charge of Kurseong could be away at the same time. Authorities, apprehending a backlash from the GNLF, have rushed additional security forces to all the three hill subdivisions of Darjeeling, Kurseong and Kalimpong. Ghising had brushed aside any possibility of threats to his life despite the ultimatum given by the Chattray Subba-led militant Gorkhaland Liberation Organisation. 'The likes of Chattray Subba are not factors in Darjeeling politics. Chattrays may come and go, but the GNLF will go on for ever,' he had told The Telegraph earlier. Subba has given a call for a renewed armed movement for a separate state of Gorkhaland. He had set the GNLF chief a deadline of December 31 to pull his councillors out of the Darjeeling Hill Council and warned him of 'dire consequences' if he did not do so. Ghising had rejected Subba's demand. Several pro-Gorkhaland organisations, too, had begun openly opposing the GNLF's authority. 'The recovery of the AK-47 rifle and a live grenade from the spot indicates that an organised group was behind the ambush,' an official said. Earlier today, Ghising had said that he had left two options for the state and Central governments for settling the Darjeeling dispute. Ghising told reporters at Pental village that the options he had offered were constitutional safeguards for the hill council under provisions of the Sixth Schedule of the Constitution or formation of a separate state of Gorkhaland.