Expressing its concerns in a statement issued by Secretary of State, Hillary Clinton, US also described as "disgraceful assault", the attack on church services at the Bayero University Kano (BUK) where two professors and several students were gruesomely killed.
Condemning attempts to inflame Christian-Muslim tensions, US expressed support for "those who recognise Nigeria's ethnic and religious diversity as one of the country's greatest strengths."
While "strongly" condemning attacks on innocent civilians in Nigeria, US said, "Our thoughts and prayers are with the families and loved ones of those who were killed and injured."
Also speaking with THISDAY in New York, former US Ambassador to Nigeria, Mr. John Campbell, agreed that the Boko Haram challenges had assumed a dangerous trend with the attacks on media offices and places of religious congregation.
Campbell, reacting to the attack on THISDAY offices in Abuja and Kaduna, and the attack at church service in BUK said: "One is an attack on the freedom of the press, the other is an attack on the freedom of religion. Both must be condemned in the strongest possible terms."
Noting the dangerous twist in the upsurge of Boko Haram attacks, the former US envoy said, "Why THISDAY was attacked, I don't know. THISDAY, of course, is a major Nigerian newspaper with circulation all over the country."
Campbell, who had consistently maintained his opposition to calls to designate Boko Haram as a foreign terrorist organisation, said the increasing wave of attacks by the sect hadn't changed his position.
He said Boko Haram appeared to him as a highly defused organisation, and "does not appear to be a tightly organised entity."
He suggested that the Boko Haram challenge should be tackled politically, arguing that Nigeria should adopt, "a political approach to northern isolation, northern alienation which are the oxygen that Boko Haram is breathing."
On recent reports showing a nexus between Boko Haram and Al Qaeda, and whether Nigeria should tackle the Boko Haram challenge the way US had been confronting Al Qaeda, Campbell said: "No, I don't think so. I think that any kind of connection that Boko Haram has with groups outside of Nigeria is not transformative."
He said he did not believe that such connections, where they exist, "shape what Boko Haram is doing."
Campbell said, "Boko Haram seems to me to be essentially focused on domestic and internal developments in Nigeria."