MUMBAI: When a 41-year-old frequent flyer landed at the international airport from Dubai on Friday, customs officials started tailing him right from the moment he walked out of the aircraft. For, they had specific tip-off that Mohammedali Kekepuram, who was returning from his fifth foreign trip in seven months, was smuggling in gold As they followed him, he went to a toilet near the immigration counter and then to the customs clearance counter. At the counter, the Air Intelligence Unit of the customs, which received the tip-off, searched him and his baggage thoroughly, but found nothing suspicious.Since the officials had specific information about him, they did not want to give up, and headed to the toilet he went to. When the officials started looking into each toilet closely, they found that push buttons of the flush tanks in two rooms were loose. And when they removed the buttons, they found that the cavity of the wall could be accessed from the other side, which was the service room. Then, airport staff were asked to open the service room. Finally, when the customs officials looked into the cavity, they found 1.1 kg gold worth Rs 34 lakh. Customs officials suspect that Mohammedali Kekepuram had smuggled in gold using the unique modus operandi during his previous trips. He was arrested and later released on bail.As only plumbers have access key to the service room, officials are probing if any of them was involved. Plumbers work in three shifts at the airport, and there are 15 staffers in each shift.On Friday, the customs also seized 1.1 kg gold worth Rs 34 lakh from a toilet of an aircraft which arrived from Dubai. The gold was wrapped in tape and concealed below the box of the tissue paper in the toilet.