Iranian and Hezbollah operatives are still seeking to attack Israeli targets in several countries, Israel's Counterterrorism Bureau indicated on Friday, warning Israeli citizens to adhere to the directives of local security forces.

The remarks, given during a press briefing, came after earlier Friday Thai security forces have upped alertness levels in the country's international airports and rail system over what local police is saying is an Israeli warning against new terror attacks.

According to a report by the Bangkok Post, Chief of Royal Thai Police Priewpan Damapong told the Transport Ministry on Thursday to place the country's six international airports on high alert. Alertness levels were raised from the normal 2 to 3.

The Bangkok Post cited a Thai government source as saying that the move followed an advisory issued by Israel to bolster airport security over intelligence reports indicating the possibility of fresh attacks.

Speaking to reporters on Friday, a top official at the Counterterrorism Bureau indicated that an investigation of Iranian nationals apprehended following the botched Bangkok bombing indicated that more attacks were in the works.

"I call on Israelis abroad to show awareness and take basic steps to reduce possible harm," the official said, adding that they should "take note of suspicious objects and refrain from taking packages from strangers" and "be attentive to the directives of local security forces."

The official added, however, security forces are not in possession of any specific information concerning a certain country in which such an attack could take place, citing only a general warning.

He added that current intelligence points at a clear Iranian involvement in all three of this week's attacks, adding that Israel was taking into account a remark by Hezbollah head Hassan Nasrallah, according to which the group planned attacks against high-ranking Israeli officials to avenge the2008 assassination of Hezbollah's deputy leader Imad Mughniyah.