North Korea has yet to respond to US outreach regarding the safety and whereabouts of a US service member who crossed the inter-Korean border into the reclusive country this week, a state department spokesperson said Wednesday.

The American soldier, identified as Pvt. 2nd Class Travis King, crossed the military demarcation line at the Joint Security Area in the Demilitarized Zone on Tuesday.

"Yesterday, the Pentagon reached out to counterparts in the Korean People's Army," state department spokesperson Matthew Miller said during a daily press briefing, referring to the North Korean military by its official name.

"My understanding is that those communications have not yet been answered," he added.

US officials earlier said that King had "willfully" and "without authorization" crossed the military demarcation line while on a group tour to the JSA.

Miller stressed that the US has a "number of channels through which we can send messages to the DPRK," referring to North Korea by its official name, the Democratic People's Republic of Korea.

"Those discussions are quite sensitive and I am not prepared to go into all the details at this time," he told the briefing.

The department spokesperson said the US is working to learn the safety of the soldier, as well as his return to the US.

"We here at the state department and the UN are all continuing to work together on this matter to ascertain information about the wellbeing and whereabouts of Private King. We are still gathering facts, and I want to be very clear that the administration has and will continue to actively work to ensure his safety and return him home to his family," said Miller.

While remaining unresponsive to US calls for dialogue, North Korea fired two short-range ballistic missiles into the East Sea early Wednesday morning, about a week after it staged its 12th intercontinental ballistic missile test since the start of last year.

"I will say that we condemn the DPRK's ballistic missile launches as we have condemned their previous ballistic missile launches," Miller said when asked about North Korea's latest missile provocation, calling them a violation of multiple United Nations Security Council resolutions.

"They pose a threat to the DPRK's neighbors and the international community. We remain committed to a diplomatic approach and call on them to engage in dialogue," he added. (Yonhap)